Scanner system

ABSTRACT

Control of illumination with illumination amplifier devices provides a basis for implementing scanner systems. Illumination amplifiers in closed illumination servo loops provide improved illumination control. An illumination control system provides precise control of camera operations for photographic and photoplotter applications. Illumination amplifier devices are used in conjunction with electronic control circuits to provide flexibility and precision in camera systems, reducing reliance on prior art mechanical devices. Illumination control circuits are presented in the form of digital gates and flip-flops and in the form of analog computational elements to provide illumination computer systems. In addition, a batch fabricated illumination computer arrangement is presented for improved implementation of illumination control systems.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of

A. ELECTRO-OPTICAL ILLUMINATION CONTROL SYSTEM Ser. No. 860,278 filed onDec. 13, 1977 by Gilbert P. Hyatt;

B. ELECTRO-OPTICAL ILLUMINATION CONTROL SYSTEM Ser. No. 169,257 filed onJuly 16, 1980 by Gilbert P. Hyatt; and

C. COMPUTER SYSTEM ARCHITECTURE Ser. No. 860,257 filed on Dec. 14, 1977by Gilbert P. Hyatt:

which application Ser. No. 860,278 is a continuation in part of thefollowing chain of applications

1. FACTORED DATA PROCESSING SYSTEM FOR DEDICATED APPLICATIONS Ser. No.101,881 filed on Dec. 28, 1970 proceedings having been terminatedtherein;

2. CONTROL SYSTEM AND METHOD Ser. No. 134,958 filed on Apr. 19, 1971;

3. CONTROL APPARATUS Ser. No. 135,040 filed on Apr. 19, 1971;

4. APPARATUS AND METHOD FOR PRODUCING HIGH REGISTRATION PHOTO MASKS Ser.No. 229,213 filed on Apr. 13, 1972 now U.S. Pat. No. 3,820,894 issued onJune 28, 1974;

5. MACHINE CONTROL SYSTEM OPERATING FROM REMOTE COMMANDS Ser. No.230,872 filed on Mar. 1, 1972;

6. COORDINATE ROTATION FROM MACHINE SYSTEMS Ser. No. 232,459 filed onMar. 7, 1972;

7. DIGITAL FEEDBACK CONTROL SYSTEM Ser. No. 246,867 filed on Apr. 24,1972 now U.S. Pat. No. 4,310,878 issued on Jan. 12, 1982;

8. COMPUTERIZED SYSTEM FOR OPERATOR INTERACTION Ser. No. 288,247 filedon Sept. 11, 1972 now U.S. Pat. No. 4,121,284 issued on Oct. 17, 1978;

9. A SYSTEM FOR INTERFACING A COMPUTER TO A MACHINE Ser. No. 291,394filed on Sept. 22, 1972;

10. DIGITAL ARRANGEMENT FOR PROCESSING SQUAREWAVE SIGNALS Ser. No.302,771 filed on Nov. 1, 1972;

11. APPARATUS AND METHOD FOR PROVIDING INTERACTIVE AUDIO COMMUNICATIONSer. No. 325,933 filed on Jan. 22, 1973 now U.S. Pat. No. 4,016,540issued on Apr. 5, 1977;

12. ELECTRONIC CALCULATOR SYSTEM HAVING AUDIO MESSAGES FOR OPERATORINTERACTION Ser. No. 325,941 filed on Jan. 22, 1973 now U.S. Pat. No.4,060,848 issued on Nov. 29, 1977;

13. ILLUMINATION CONTROL SYSTEM Ser No. 366,714 filed on June 4, 1973now U.S. Pat. No. 3,986,022 issued on Oct. 12, 1976;

14. DIGITAL SIGNAL PROCESSOR FOR SERVO VELOCITY CONTROL Ser. No. 339,817filed on Mar. 9, 1973 now U.S. Pat. No. 4,034,276 issued on July 15,1977;

15. HOLOGRAPHIC SYSTEM FOR OBJECT LOCATION AND IDENTIFICATION Ser. No.490,816 on July 22, 1974 now U.S. Pat. No. 4,209,853 issued on June 24,1980;

16. COMPUTERIZED MACHINE CONTROL SYSTEM Ser. No. 476,743 filed on June5, 1974;

17. SIGNAL PROCESSING AND MEMORY ARRANGEMENT Ser. No. 522,559 filed onNov. 11, 1974 now U.S. Pat. No. 4,209,853 issued on June 24, 1980;

18. METHOD AND APPARATUS FOR SIGNAL ENHANCEMENT WITH IMPROVED DIGITALFILTERING Ser. No. 550,231 filed on Feb. 14, 1975 now U.S. Pat. No.4,209,843 issued on June 24, 1980;

19. ILLUMINATION SIGNAL PROCESSING SYSTEM Ser. No. 727,330 filed onSept. 27, 1976 now abandoned;

20. PROJECTION TELEVISION SYSTEM USING LIQUID CRYSTAL DEVICES Ser. No.730,756 filed on Oct. 7, 1976 now abandoned;

21. INCREMENTAL DIGITAL FILTER Ser. No. 754,660 filed on Dec. 27, 1976;

22. ANALOG READ ONLY MEMORY Ser. No. 812,285 filed on July 1, 1977;

23. MEMORY ARCHITECTURE Ser. No. 844,765 filed on Oct. 25, 1977;

24. INTELLIGENT DISPLAY SYSTEM Ser. No. 849,733 filed on Nov. 9, 1977;

25. DIGITAL SOUND SYSTEM FOR CONSUMER PRODUCTS Ser. No. 849,812 filed onNov. 9, 1977; and

26. HIGH INTENSITY ILLUMINATION CONTROL SYSTEM Ser. No. 860,277 filed onDec. 13, 1977;

which application Ser. No. 169,257 is a continuation in part of saidapplications Ser. No. 366,714; Ser. No. 730,756; Ser. No. 860,277; andSer. No. 860,278:

which application Ser. No. 860,257 is a continuation in part of saidapplication Ser. No. 101,881:

all by Gilbert P. Hyatt:

wherein the benefit of the filing dates of all of the above referencedapplications is herein claimed under 35 USC 120, 35 USC 121, and otherauthorities provided therefor: and

wherein the instant application is further related to applications:

27. INTERACTIVE CONTROL SYSTEM Ser. No. 101,449 filed on Dec. 28, 1970by Lee, Cole, Hirsch, Hyatt, and Wimmer now abandoned in favor of acontinuing application;

28. ADAPTIVE ILLUMINATION SOURCE INTENSITY CONTROL DEVICE Ser. No.152,105 filed on June 11, 1971 by Lee, Wimmer, and Hyatt now U.S. Pat.No. 3,738,242 issued on June 12, 1973;

ADAPTIVE ILLUMINATION CONTROL DEVICE Ser. No. 325,792 filed on Jan. 22,1973 by Lee, Wimmer, and Hyatt now U.S. Pat. No. 3,927,411 issued onDec. 16, 1975;

30. ILLUMINATION CONTROL SYSTEM Ser. No. 327,918 filed on Jan. 30, 1973by Lee, Wimmer, and Hyatt now U.S. Pat. No. 3,818,496 issued on June 18,1974;

31. INTERACTIVE CONTROL SYSTEM Ser. No. 354,590 filed on Apr. 24, 1973by Lee, Cole, Hirsch, Hyatt, and Wimmer now U.S. Pat. No. 4,038,640issued on July 26, 1977;

32. MEANS AND METHOD FOR SELECTIVELY CONTROLLING ANIMALS Ser. No.438,328 filed on Jan. 31, 1974 by Lee and Hyatt now U.S. Pat. No.3,897,753 issued on Aug. 5, 1975;

33. ADAPTIVE ILLUMINATION CONTROL DEVICE Ser. No. 495,349 filed on Aug.7, 1974 by Lee, Wimmer, and Hyatt;

34. ELECTRONIC LOCK AND KEY SYSTEM Ser. No. 583,136 filed on June 2,1975 by Lee and Hyatt now U.S. Pat. No. 4,036,178 issued on July 19,1977; and

35. ELECTRO-OPTICAL PRINTER Ser. No. 754,647 filed on Dec. 27, 1976 byStanly and Hyatt now U.S. Pat. No. 4,236,223 issued on Nov. 25, 1980;

36. PULSEWIDTH MODULATED FEEDBACK ARRANGEMENT FOR ILLUMINATION CONTROLSer. No. 874,446 filed on Feb. 2, 1978 by Gilbert P. Hyatt;

37. ILLUMINATION SIGNAL PROCESSING SYSTEM Ser. No. 874,444 filed on Feb.2, 1978 by Gilbert P. Hyatt; and

38. ILLUMINATION SIGNAL PROCESSING SYSTEM Ser. No. 874,445 filed on Feb.2, 1978 by Gilbert P. Hyatt:

wherein all of the above-mentioned applications are hereinincorporated-by-reference as if fully set forth at length herein.

TABLE OF CONTENTS SECTION

Abstract of the Disclosure

Cross Reference to Related Applications

Background of the Invention

Field of the Invention

Description of the Prior Art

Summary of the Invention

Brief Descriptions of the Drawings

Detailed Description of the Invention

Illumination Amplifier Devices

Digital Excitation

Analog Excitation

Schematic Notation

Illumination Computer

Digital Control Arrangements

Analog Control Arrangements

Batch Fabricated Arrangement

Closed Loop Control

Flat Plane Configuration

Discrete Illumination Device

Light Pen Arrangement

Illuminated Switches

Color Control

Control of Natural Illumination

Illumination Control for Buildings

Illumination Control for Vehicles

Illumination Shade

Temperature Control

Control of Artificial Illumination

Lamp Control

Dimmer Control

Flasher Control

Camera Systems

Image Rotation Control

Aperture Control

Shutter Control

Photographic Camera System

Source Illumination Control

Audience Display System

Illumination Chopper, Scanner, and Modulator

Illumination Modulators

Camera System Improvements

Movie Camera System

Computer Control Arrangement

Traffic Light Control

Operator Panel

Improved Slide Projector

Segment Arrays

Multiple Electrode Logic

Fringe Control

Integrated Electro-Optic Devices

Improved Fiber Optic Arrangement

Additional Considerations Pertinence of MaterialIncorporated-By-Reference

Projection Display Arrangement

Alternate Scanner Embodiment

Spacial Control of Illumination

Audience Display System, Additional Features

Further Considerations

Electro-Optical Thermal Design

Large Panel Construction

Antecedent Basis For Projection Disclosure

Pulse Modulated Control

Time-Domain Pulse Modulation

Optical Effects

Light Organ

Further Spacial Control Features

SCOPE AND LIMITATIONS

IN THE CLAIMS

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to illumination control systems and, inparticular, scanner systems using illumination amplifiers.

2. Description of the Prior Art

Control of illumination has been accomplished in the prior art withmechanical devices. The well known aperture and shutter of a camera arecommon mechanical devices for controlling light. Other prior artillumination control arrangements are described hereafter.

In the photoplotter field, a photohead is used to control light forexposing film. Mechanically positioned filters and shutters are used forillumination control such as described in U.S. Pat. No. 3,330,182 issuedin July 1967.

The prior art and subsequent art in illumination control is furtherdefined in the art-of-record of the parent application Ser. No. 366,714including U.S. Pat. Nos. 3,790,901 to White et al; 3,778,791 to Lewickiet al; 3,764,213 to O'Meara; 3,744,906 to Sato et al; 3,720,923 to Chenet al; 3,713,042 to Kinsel; 3,705,758 to Haskal; 3,696,344 to Feinleibet al; 3,670,202 to Paine et al; 3,558,892 to Seeley; 3,473,084 toDodge; and 3,427,458 to Parfomak et al and in the art-of-record of theparent application Ser. No. 730,756 including U.S. Pat. Nos. 3,981,002to Gardner; 3,798,452 to Spitz et al; No. 3,786,486 to Torresi;3,707,323 to Kessler et al; 3,702,723 to Borden Jr.; 3,700,805 toHanlon; 3,666,881 to Stein; 3,647,959 to Schlesinger et al; 3,641,264 toMacovski; 3,627,408 to Fergason; 3,605,594 to Gerritsen; 3,576,364 toZanoni; 3,566,021 to Jakes Jr.; 3,544,711 to De Bitetto; 3,541,254 toOrthuber; 3,527,879 to Pritchard; 3,444,316 to Gerritsen; 3,231,746 toGoodrich; and 2,169,838 to Herbst which are hereinincorporated-by-reference. The prior art in illumination control isstill further defined in the art-of-record of the referenced relatedapplications including U.S. Pat. Nos. 3,836,916 to Wiley; 3,721,164 toKuttigen; 3,703,858 to Canfora; 3,695,154 to Webster; 3,686,675 to Faul;3,648,578 to Ritchie; 3,610,119 to Gerber; 3,595,147 to Blattner;3,565,524 to Pabst et al; 3,498,711 to Ables et al; 3,458,253 to Hansen;3,354,806 to DeLang et al; 3,330,182 to Gerber et al; 3,323,414 toRitchie et al; and 3,048,093 to Loro.

SUMMARY OF THE INVENTION

The present invention provides a scanner system for improved control ofillumination. This illumination control system can use solid statedevices for electronic control of illumination, with reduced dependenceon mechanical control devices.

Illumination amplifiers are provided which control thetransmissivity-reflectivity characteristic as a function of appliedexcitation. Such amplifier devices may be controlled in a digitalfashion or in an analog fashion using electronic signals for control ofillumination. Also, servo arrangements are provided for precise controlof illumination.

Availability of a basic illumination processing component, theillumination amplifier, permits a wide variety of illuminationprocessing systems to be implemented. These systems include illuminationcomputers of both the digital and the analog variety, photographiccameras, photoplotter systems, illumination controls for vehicles suchas automobiles, light and heat control systems for inhabited structures,and other such illumination systems.

Various control configurations may be provided including open and closedloop controls, analog and digital controls, illumination amplifierexcitation arrangements, and other control configurations.

An object of this invention is to provide an improved illuminationcontrol system.

A further object of this invention is to provide a solid stateillumination control system.

A still further object of this invention is to provide an illuminationcontrol system for an inhabited structure.

Yet a further object of this invention is to provide illuminationcomputer arrangements including both analog and digital illuminationarrangements.

Another object of this invention is to provide improved excitation andcontrol devices for illumination amplifier arrangements.

Yet another object of this invention is to provide illumination closedloop servos for precision control.

Still a further object of this invention is to provide an improveddisplay arrangement.

Yet another object of this invention is to provide an improvedilluminated switch arrangement.

Yet still another object of this invention is to provide improvedchopper, scanner and modulator arrangements.

Still another object of this invention is to provide improvedphotographic control arrangements.

Still another object of the present invention is to provide an improvedprojection display arrangement.

Still another object of the present invention is to provide an improvedheat transfer arrangement.

Still another object of the present invention is to provide an improvedlarge panel arrangement.

The foregoing and other objects, features, and advantages of thisinvention will become apparent from the following detailed descriptionof preferred embodiments of this invention, as illustrated in theaccompanying drawings.

BRIEF DESCRIPTIONS OF THE DRAWINGS

A better understanding of the invention may be had from a considerationof the following detailed description taken in conjunction with thefollowing drawings, in which:

FIG. 1 is a block diagram of an illumination control arrangement inaccordance with the present invention.

FIG. 2 illustrates various excitation arrangements for illuminationamplifiers in schematic and waveform diagrams comprising FIG. 2A showinga digital excitation arrangement, FIG. 2B showing pulse modulationwaveforms, FIG. 2C showing an analog excitation arrangement, and FIG. 2Dshowing pulse width modulation waveforms.

FIG. 3 illustrates illumination arrangements in schematic and blockdiagram form comprising FIG. 3A showing a generalized control network,FIG. 3B showing operation of a single illumination amplifier, FIG. 3Cshowing an exclusive-OR and coincidence logical arrangement, FIG. 3Dshowing a flip-flop logical arrangement, FIG. 3E showing an analogexponential arrrangement, and FIG. 3F showing an analog implicite servoarrangement.

FIG. 4 is a schematic diagram of a batch fabricated illumination controlarrangement.

FIG. 5 is a schematic and block diagram illustrating a closed loopcontrol for an illumination amplifier arrangement.

FIG. 6 illustrates display arrangements in schematic, waveform, andblock diagram form comprising FIG. 6A showing a batch fabricated displayarrangement, FIG. 6B showing a batch fabricated illuminated switcharrangement, FIG. 6C showing an illuminated switch schematic diagram,FIG. 6D showing a control arrangement for colored illumination, and FIG.6E showing pulse modulation control waveforms.

FIG. 7 is a schematic and block diagram illustrating illuminationcontrol arrangements for buildings and for vehicles comprising FIG. 7Ashowing a first window and a louver illumination control arrangement,FIG. 7B showing a second window illumination control arrangement, FIG.7C showing an artificial illumination control arrangement, and FIG. 7Dshowing a temperature control arrangement.

FIG. 8 is a schematic and block diagram illustrating illuminationcontrol arrangements for camera systems comprising FIG. 8A showing animage rotation arrangement, FIG. 8B showing a square aperturearrangement, FIG. 8C showing a circular aperture arrangement, and FIG.8D showing an illumination control arrangement for a camera.

FIG. 9 is a schematic and block diagram illustrating a camera controlsystem in accordance with the present invention comprising FIG. 9Ashowing a detailed camera control arrangement, FIG. 9B showing acomputer control arrangement, and FIG. 9C showing a special purposecontrol arrangement.

FIG. 10 is a schematic and block diagram illustrating a photoplottersystem in accordance with the present invention.

FIG. 11 is a schematic and block diagram illustrating a display systemin accordance with the present invention.

FIG. 12 is a schematic and block diagram illustrating an illuminationscanner, chopper, and modulator system in accordance with the presentinvention comprising FIG. 12A showing a first electro-opticalembodiment, FIG. 12B showing a second electro-optical embodiment, FIG.12C showing a first control embodiment, FIG. 12D showing a secondcontrol embodiment, and FIG. 12E showing a third electro-opticalembodiment.

FIG. 13 is a schematic and block diagram illustrating an interspersedarray of electro-optical elements for illumination control.

FIG. 14 is a schematic and block diagram illustrating a projectiondisplay arrangement comprising FIG. 14A showing a single projectorarrangement, FIGS. 14B through 14E showing multiple image projectionarrangements, and FIG. 14F showing a TV projection embodiment.

FIG. 15 is a schematic and block diagram illustrating spacial controlcomprising FIG. 15A showing a rectangular symetry arrangement, FIG. 15Bshowing a circular symetry arrangement, FIG. 15C showing a watchembodiment, and FIG. 15D showing a camera control embodiment.

FIG. 16 is a structural arrangement illustrating alternate embodimentsof a projection illumination amplifier arrangement, heat transferarrangement, and large panel arrangement comprising FIG. 16A showing ageneral heat transfer arrangement, FIG. 16B showing a picture frame heattransfer arrangement, FIG. 16C showing an edge heat transferarrangement, FIG. 16D showing a reflective mode back-mounted heattransfer arrangement, FIG. 16E showing heat transfer devices, FIG. 16Fshowing a projection display system employing various heat transferarrangements, and FIG. 16G showing various heat transfer and large panelconstruction features in accordance with the present invention.

FIG. 17 is a block and schematic diagram arrangement showing pulsemodulated and display arrangements comprising FIG. 17A showing a pulsemodulation circuit, FIG. 17B showing a pulse modulation program flowdiagram, FIGS. 17C and 17D showing a liquid crystal display arrangement,and FIG. 17E showing a liquid crystal toy.

By way of introduction of the illustrated embodiment, the componentsshown in FIGS. 1 through 17 of the drawings have been assigned generalreference numerals and a brief description of such components is givenin the following description. The components in FIGS. 1-16 have ingeneral been assigned three or four digit reference numerals wherein thehundreds digit of the reference numerals corresponds to the figurenumber. For example, the components in FIG. 1 have reference numeralsbetween 100 and 199 and the components in FIG. 2 have reference numeralsbetween 200 and 299 except that the same component appearing insuccessive drawing figures has maintained the first reference numeral.The components in FIG. 17 has not been numbered as discussed above, buthas been assigned 900 series reference numerals to be consistent withthe corresponding figure in the referenced copending applications.

DETAILED DESCRIPTION OF THE INVENTION

The illumination control system of this invention can take any number ofpossible forms. Preferred embodiments of several features of the presentinvention are shown in the accompanying figures and will be described indetail hereafter.

The system of this invention is exemplified by the simplified blockdiagram shown in FIG. 1. An illumination source 100 generatesillumination 102 which is directed to an illumination amplifier 104. Theillumination 102 from the source 100 may be defined as sourceillumination. Source illumination 102 may be raw illumination or may becontrolled by source illumination control devices such as will bedescribed hereafter. Illumination amplifier 104 may be a variableillumination transmissivity device such as a well known liquid crystaldevice. Controlled illumination 106 from illumination amplifier 104 isdirected to illumination receiver 112. This controlled illumination 106may be controlled by reflection, transmission, or by othercharacteristics of illumination amplifier 104. Also, controlledillumination 106 may comprise a plurality of illumination signals suchas one or more reflected components and one or more transmittedcomponents, where one of these illumination components 108 may perform afirst illumination task such as exposing an illumination sensitivemedium which may be receiver 130 and another of these illuminationcomponents 110 may perform a second illumination task such asilluminating an illumination sensitive feedback transducer which may bereceiver 134. The illumination sensitive medium provides an illuminationreaction in response to the illumination such as a chemical reaction ina photographic film medium or a thermal reaction in an illuminationabsorbing medium, wherein exposure of such mediums are discussed indetail hereinafter. One arrangement comprising control of a plurality ofillumination signals will be discussed hereafter with reference to FIGS.3, 4, and 5.

Illumination receiver 112 may include an arrangement for illuminating anillumination sensitive medium 130 such as a film and may include afeedback transducer 134 for providing feeeback signal 114 for control ofillumination.

Illumination feedback signals 114 may be used to control illuminationamplifiers 104, may be used to control illumination sources 100 and maybe used as feedback to command devices 127. Feedback signal processor116 provides signal processing for feedback signals 114 and may includeillumination amplifier feedback signal processor 118 for generating anillumination amplifier feedback signal 120 for control of illumination106 by amplifiers 104 with processed command signals 133; may furtherinclude illumination source feedback signal processor 122 for generatingillumination source feedback signals 124 for control of illumination 102by source 100 with processed command signals 132; and may still furtherinclude illumination command device feedback signal processor 138 forgenerating illumination command device feedback signals 139 for controlof command signals 126 by command devices 127.

Illumination command signal 126 may be open loop or closed loop inputcommands from command devices 127. Such a command device may be a manualdevice for operator control such as a switch arrangement or may be anautomatic device such as a digital computer, an analog computer, orother such well known command arrangements. Command signal processor 128may generate illumination source command signals 132 to command source100 to generate source illumination 102; or may generate illuminationamplifier command signals 133 to command amplifier 104 to controlillumination 106; or both.

Illumination Amplifier Devices

An amplifier may be described as a device that permits a relativelylarge amount of energy to be controlled with a relatively small amountof control energy. An illumination amplifier is herein intended to meana device that controls illumination with a control signal which may be alow energy electrical control signal in a preferred embodiment. Priorart illumination controls require high energy control signals to exciteillumination sources such as incandescent lamps or to drive mechanicaldevices such as shutters. In a preferred embodiment, the system of thisinvention requires a low level electrical signal to excite anillumination amplifier such as a liquid crystal device for control ofillumination.

Illumination amplifier arrangements are herein discussed relative toelectrical excitation signals controlling thereflectivity-transmissivity characteristics of illumination amplifiersfor control of illumination signals. Illumination amplifiers may also becontrolled with other signals 135 such as temperature conditions forcontrolling the reflectivity-transmissivity characteristic of atemperature sensitive cholesteric liquid crystal device. Similarly,various control signals such as electrical and temperature signals 133and 135 may be used to control other parameters of illumination such ascombinations of reflectivity, transmissivity, absorption, refraction,and filtering of illumination.

It should be understood that an actual illumination device such as anillumination amplifier may not be a perfect reflector or transmitter ofillumination and may absorb, transmit, and reflect a certain amount ofillumination even when controlled to be fully transmissive or fullyreflective. For simplicity in describing this invention, a perfectillumination amplifier will be assumed without absorbtion and with theability to completely control reflectivity and transmissivity.

For simplicity of presentation, illumination amplifiers may be shownwithout electrodes, excitation and control arrangements. The electricalexcitation can be provided with well known arrangements and may not bediscussed in detail herein. Illumination amplifiers discussed andillustrated herein are intended to include suitable electrode andexcitation arrangements even though these electrode and excitationarrangements may not be specifically illustrated.

This invention relates to illumination amplifiers which may includeelectro-optical and electro-chemical devices exemplified with liquidcrystal devices for controlling illumination with electrical signals. Inorder to exemplify the teachings of this invention, arrangements may bedescribed using illumination amplifiers such as the well known liquidcrystal panels.

Liquid crystal devices may be used to exemplify features of thisinvention. Liquid crystal devices are well known in the art and are inuse for numeric display devices. Typical devices are sold by IndustrialElectronic Engineers, Inc. of Van Nuys, Calif.such as series 1500-01; byAmerican Micro-Systems, Inc. of Santa Clara, Calif. such as model no.21450; by RCA of Somerville, N.J. and by other well known sources. Suchliquid crystal devices are typically composed of only microns thickliquid crystal material contained between glass substrates or plateswith transparent electrodes etched on a glass substrate. When theelectrodes are excited, the liquid crystal material changes thetransmissivity and reflectivity characteristics. Liquid crystal materialmay be of the nematic, smectic, cholesteric, and other well known types.Excitation is typically alternating current of 60 Hz frequency, 20 voltsand with only micro-amperes of current. Liquid crystal displays arefurther discussed in the March 1972 issue of Computer Design Magazine onpages 77 and 78 entitled A Comparison and Review of Digital Readouts bySidney Davis and in the November 1971 issue of the Proceedings of theIEEE entitled Liquid Crystal Matrix Displays by Lehner et al whereinthese articles are incorporated herein by reference. Because liquidcrystals and the associated arrangements such as alternating currentexcitation devices are well known in the display technology, a liquidcrystal display device and the associated excitation may be shown inblock diagram or schematic form without specifically showing these wellknown excitation arrangements. Similarly, because the selective controlof areas of liquid crystal devices such as the control of displaysegments by etched electrodes are well known in the art, controlledareas of variable transmissivity and reflectivity characteristics needbe shown only in the form and shape of the desired controlled areawithout showing the construction, selective etching, and excitationwhich are well known in the art.

For simplicity of discussion, illumination amplifier arrangements may bediscussed with respect to simple area control of illumination. Severalembodiments are presented herein using amplifier segments such asconcentric rings (FIG. 8C) bands or stripes (FIGS. 7B and 8B) andpatterns (FIGS. 7C and 8A). It will become obvious that more complexarrangements may be provided such as intricate patterns of controllableamplifiers. Such a pattern may be a dot pattern similar to the wellknown half tone dot patterns widely used in the printing art. Otherpatterns will become obvious to those skilled in the art.

Digital Excitation

Digital control of an illumination amplifier is relatively simple whencompared to analog control, where a digital control signal may be eitheron for exciting an illumination amplifier or off for non-exciting anillumination amplifier. An alternating current excitation may be usedwith a liquid crystal type of illumination amplifier. In such anarrangement, an electronic switch may be used to provide controlledexcitation for the amplifier by selectively switching a sinusoidalexcitation signal.

A digital excitation arrangement 201 is shown in FIG. 2A, where a wellknown flip-flop 200 is arranged to selectively generate a square wave202 as output signal Q on line 204. When the F input 206 is true, theflip-flop 200 will change state for each clock pulse 208, therebygenerating an output signal 204 at a frequency that is half of thefrequency of clock signal 208. When the F input 206 is false, flip-flop200 will maintain its output state and will not be responsive to theclock signal. Therefore, flip-flop 200 will digitally generate analternating excitation signal 202 at half the frequency of clock signal208 as controlled by logic signal 206. The digital clock signal C 208may be the output of count down logic to provide a clock pulse at thedesired frequency.

For one digital excitation embodiment, a continuous squarewave 202 isgenerated to provide an alternating excitation signal such as with inputsignal 206 to flip-flop 200 maintained true for a continuous squarewave202 as output signal 204. Output signal 204 may be selectively gatedwith AND gates 210 controlled with select signals 212 to selectivelygenerate amplifier excitation which may be square wave excitationsignals 214 for a plurality of illumination amplifier devices.

It has been found that digital excitation has particular advantagesbecause of (1) the well known low power characteristic of switchingdevices as compared to linear amplifying devices and (2) the convenienceof generating squarewave signals with digital circuits such as flip-flop200. Also, the low power requirements of many illumination amplifierdevices may permit direct excitation with logic signals 204 and 214.

As described herein, illumination sensitive transducers may be used toconvert an illumination signal into an electrical signal for control ofan illumination amplifier. In such an arrangement, the transducer may bea photo-sensitive switch such as the well known family of gatedrectifiers such as silicon controlled rectifier (SCR) type devices.These gated rectifier devices may be arranged for gating with anillumination signal to generate alternating excitation directly from anillumination signal. Transducers 216 may be such illumination sensitivegated rectifier devices. Devices 216 may be arranged to be responsive toillumination signals 218 to switch an excitation signal such as squarewave 204 to output lines 220 to excite various illumination amplifiers.The square wave nature of the excitation signal 204 provides forautomatically extinguishing of transducers 216 when illumination gatesignal 218 is removed, thereby removing squarewave excitation fromamplifier control lines 220. The well known gated rectifier technologywill permit other excitation arrangements such as SCR control ofsinusoidal signals. Gated rectifier devices are herein intended toinclude the well known group of gated switches characterized by SCRdevices and including triacs and other SCR type devices. Typical devicesare the General Electric photo SCR type H10C1, the General Electricphoto switch type LiV, and other photo sensitive devices.

Excitation arrangement 201 provides a detailed illustration of a commandarrangement may be part of the illumination control system illustratedin FIG. 1 where excitation arrangement 201 may be included in commandsignal processor 128; where command signals 126 from command device 127may include command signal F 206 to flip-flop 200, command signals 212to gates 210 and command signals 215 to flip-flop 213; and whereprocessec command signls 132 and 133 may include processed commandsignals 204, 214, and 220. In another embodiment, illumination signals106 may include illumination signals 218, transducers 134 may includegated rectifiers 216, and transducer signals 114 may include transducersignals 220.

Analog Excitation

Analog control of an illumination amplifier is relatively more complexthan the digital control discussed above, where the analog controlsignal may take any one of a range of values and may be continuouslyadjustable over that range. Such an analog control arrangement may haveparticular advantages when compared to a digital control arrangementsuch as continually variable transmissivity-reflectivity characteristicsfor analog operations including closed loop illumination servoarrangements.

Analog excitation devices may be implemented as pulse modulated devicesor as amplitude devices. Illumination amplifiers may be able to operateon analog amplitude signals permitting a relatively simple excitationarrangement, but many types of illumination amplifiers such as certainliquid crystal devices cannot directly utilize analog amplifier signalsand, therefore, must be excited with pulse modulated signals. A pulsemodulated signal operates on the principal of constant amplitude andvariable duty cycle, including pulse width modulated and pulse ratemodulated analog signals.

An arrangement using analog amplitude excitation depends on the abilityof an illumination amplifier to control an amplifier characteristic suchas the transmissivity-reflectivity characteristic discussed herein as afunction of or proportional to the analog amplitude of the excitationsignal. Analog amplitude signals are relatively simple to obtain becausemany devices such as illumination transducers provide output electricalsignals proportional to the input illumination signals. Analog commanddevices that provide analog amplitude outputs such as digital-to-analogconverters and potentiometers are well known in the art and will bediscussed hereafter in relation to FIGS. 2C and 9B.

An arrangement using pulse modulated analog excitation is more generallyapplicable than an analog amplitude arrangement because certain types ofillumination amplifiers may not be controllable with analog amplitudesignals. Also, certain types of illumination amplifiers may be moreprecise when controlled with pulse modulated (on-off) signals. Pulsemodulated signals will now be described with reference to FIG. 2B.

Pulse width modulating control is illustrated with signals 222 and 223;where signal 222 has a low duty cycle with a narrow pulse 226 and signal223 has a higher duty cycle with a wider pulse 227. As the analogparameter varies from zero to maximum, the pulse width varies fromvirtually no pulse through a range of widening pulses to the extreme ofthe signal being in the high state 226, 227 virtually continuously.Therefore the area under the pulses known in the art as the duty cyclevaries proportionally with the analog parameter.

Pulse rate modulation control is illustrated with signals 224 and 225;where signal 224 has a low duty cycle with a low pulse rate or a widespacing 228 between pulses 229 and 230 and where signal 225 has a highduty cycle with a high pulse rate or a narrow spacing 231 between pulses232 and 221. As the analog parameter varies from zero to maximum, thepulse rate varies from virtually no pulses through a range of greaternumbers of pulses over a given period to the extreme of the signal beingin the high state virtually continuously. Therefore, the area inside thepulses or the duty cycle varies proportionally with the analogparameter. For pulse rate modulation, pulses 229, 230, 232, and 22 mayhave a constant pulse width as contrasted to pulse width modulationpulses described above.

For pulse modulation control, a pulse frequency or frequency range maybe selected based upon the dynamic requirements of the application. Fora visual application, a rate of 30 Hz or greater may be required becausethe human eye may detect flicker at lower frequencies. For variouscontrol applications, pulse rates may be permitted below the rate of apulse every several seconds or pulse rates may be required exceedingthousands of pulses per second. A particular illumination amplifier maybe selected for it's dynamic response characteristics to satisfy thedynamic requirements of the system.

An analog amplitude signal characteristic may be obtained from a pulsemodulated signal by integrating pulse modulated signals. Thisintegration may be inherent in the system such as with an illuminationamplifier, a transducer, or the human eye. In certain systems it may benecessary to provide filtering or integration such as with reactiveelectronic components in electronic circuits or other well knownelectrode and illumination integrating devices.

Pulse modulation devices may be analog amplitude to pulse modulationconverters which accept analog amplitude inputs and generate pulsemodulated outputs. A preferred embodiment of an analog control mayinclude a pulse width modulation device, although other pulse modulationdevices may be used such as the well known reset integration pulse ratemodulation device.

A preferred embodiment of a pulse width modulation arrangement is shownin FIG. 2C and will be described with respect to the waveforms shown inFIG. 2D. Modulator 222 generates a ramp waveform 223 on line 233 whichprovides a reference input to comparitors 234. Each comparator 234compares a ramp signal 233 with an input analog signal 235 to generate apulse width modulated output signal 236. Output signals 236 are pulsewidth modulated signals similar to waveforms 237 and 238; where eachoutput signal 236 such as waveforms 237 and 238 goes true at the startof ramp 223 and remains true as long as the ramp 223 has an amplitudethat is less than an input signal 235. When ramp 233 makes a transitionto being more positive than an input signal 235, a corresponding outputsignal 236 goes false providing a pulse that has a width proportional tothe amplitude of the input analog signal.

Ramp generator 239 is composed of counter 240 and digital-to-analogconverters 241. Counter 240 is a well known digital counter that countsto a maximum value, then overflows to a zero value, then counts back upto the maximum value. Digital output signals 242 of counter 240 excite awell known digital-to-analog (D/A) converter 241 that may include aweighted resistor ladder and analog switches, but may be other wellknown D/A converter arrangements. Converter 241 provides an analogoutput 233 proportional to the input count parameter 242. Therefore,output signal 233 is a sawtooth waveform 223 that is reset 243 whencounter 240 overflows and that generates a ramp 244 as the count incounter 240 increases.

For illustrative purposes, analog voltage levels A 245 and B 246 aresuperimposed on ramp 244 of waveform 223. At the beginning of the ramp,the output signals 236 of two of the comparitors 234 are shown aswaveforms 237 and 238 related to a pair of input signals 235 havingamplitudes A 245 and B 246, respectively. As ramp 244 increases butremains below input signal thresholds 245 and 246, output signals 237and 238 remain high. As ramp 244 makes a transition through amplitude A245, the ramp amplitude 244 becomes greater than the input signalamplitude 245 and a comparator 234 causes the output signal 237 to makea transition 247 to the low state. Therefore, pulse width 248 isproportional to amplitude A 245. Similarly, as the ramp amplitude 244makes a transition through amplitude B 246, a comparator 234 causes theoutput signal 238 to make a transition 249 to the low state. Therefore,pulse width 250 is proportional to amplitude B 246 which isproportionally greater than pulse width 248 by the same amount thatamplitude B 246 is greater than amplitude A 245.

A computer or other digital command device can provide a command inputto an illumination amplifier such as with amplifier excitation signals236. In one embodiment, computer 251 generates output commands 252 to atleast one D/A converter 253, which provides a command signal 235 to acomparitor 234 for generating a pulse width modulated signal 236 tocontrol an illumination amplifier. Other digital command arrangementsfor controlling analog illumination devices will become obvious to thoseskilled in the art.

A servo summing junction may be incorporated into modulator 222 assumming junction 238 comprising well known arrangements such as summingresistors 237. An analog command signal such as command signal C 126 maybe summed with a negated feedback signal such as feedback signal-F 120to generate an error (difference) signal ε 235A as an analog commandsignal. Pulse width modulator 222 will then generate a pulse widthmodulated excitation signal 236A with comparator 234A for controlling anillumination servo amplifier. Summing junction 238 and modulator 222will be further discussed hereafter in relation to a servo systemillustrated in FIG. 5.

Comparators 234 are well known in the art and may be Fairchildintegrated circuit comparator serial no. 710.

Modulator 222 has been found to have particular advantage for a systemrequiring a plurality of independent pulse width signal conversionsbecause much of the control devices are common to all conversionchannels, such as counter 240 and converter 241 being common to allchannels 236.

Excitation arrangement 222 provides a detailed illustration of a commandarrangement that may be part of the illumination control systemillustrated in FIG. 1 where command device 127 may include computer 251and A/D converter 253; where command signal 126 from command device 127may include command signals 235; where command signal processor 128 mayinclude counter 240, converter 241, and comparators 234; and whereprocessed command signals 132 and 133 may include processed commandsignals 236.

An alternate embodiment of a pulse modulated excitation arrangement isprovided in the copending applications referenced above. This alternateembodiment provides pulse modulated waveforms directly as outputs from adigital computer. Other arrangements for generating pulse modulatedwaveforms will become obvious to those skilled in the art.

Schematic Notation

In order to discuss various inventive features in a simple form, it willbe necessary to adapt an illumination schematic notation. Symbolicnotations, designations, and signals may be defined in a form similar tothat used for electronic schematics.

An illumination notation will now be defined with reference to FIG. 3A.

Electrical signals such as signal 318 are shown having a single linefrom source to destination and may or may not have an arrowhead at areceiving device such as device 319.

Illumination signals such as signals 301, 302, and 304 are shown havinga double line from source to destination with an arrowhead at areceiving device. An illumination notation may be used herein showng anincident or input illuminating signal for an illumination amplifier withan arrowhead at the amplifier such as shown for signals 301 and 316incident on amplifiers 300 and 310 respectively. Other notations mayshow a transmitted signal with the arrowhead directed away from theamplifier from which it is transmitted colinear with an input signalsuch as transmitted signal 302 and may further show a reflected signalfrom an amplifier non-colinear with an input signal and with thearrowhead directed away from the amplifier from which it is reflectedsuch as with reflected signal 304.

Illumination can be directed in the required direction with well knownillumination processing devices such as mirrors and prisms. Therefore,illumination may be shown and described herein in schematic form withoutillustrating the routing devices for simplified discussion. For example,reflected and transmitted illumination signals 302 and 304 shown in FIG.3A are directed in approximately the proper directions such as with theangle of incidence 306 equal to the angle of reflection 307, butillumination signals 108 and 110 shown in FIG. 1, which may correspondto illumination signals 302 and 304 of FIG. 3, are not directionallyoriented in their schematic form. It will be obvious to those skilled inthe art from the schematic representations and descriptions as to theproper directions for illumination and the proper illuminationprocessing arrangements to direct illumination in those directions.

A diagonal block will be used herein to define an illumination amplifierin schematic form such as diagonal lines 300, 310, and 312. A symbolicdesignation may be assigned to an illumination amplifier such as an Aand a B for amplifiers 300 and 312 respectively. An amplifier symbol notonly identifies the associated amplifier, but is also intended to definethe associated excitation signal and, therefore, the operating conditionof the amplifier.

A digital notation will now be defined with reference to amplifier 300which has an associated logical symbol A. If A is true, then amplifier300 is defined to be transmissive, with transmitted illumination 302being maximized and reflected illumination 304 being minimized.Illumination 302 will be defined herein as a true condition associatedwith amplifier 300 and will be designated A. Similarly, if A is false(A), then amplifier 300 is defined to be reflective; with reflectedillumination 304 being maximized and transmitted illumination 302 beingminimized. Therefore, illumination 304 will be defined herein as a falseor complement condition associated with amplifier 300 and will bedesignated A. If illumination 301 is a logical function defined as F₁,it will then be obvious that illumination 302 will be logical functionA·F₁ and that illumination 304 will be logical function A·F₁. The dotsymbol is defined as a logical AND symbol as is well known in thedigital computer art. If illumination 302 is designated F₂ andillumination 304 is designated F₃, then the logical equations can bedescribed as:

    F.sub.2 =A·F.sub.1                                equation (1)

    F.sub.3 =A·F.sub.1                                equation (2)

An analog notation will now be defined for amplifier 300. Forproportional control of amplifier 300, illumination signals 302 and 304can be controlled as a function of control signal A. Therefore, terms A,F₁, F₂, and F₃ can be used to designate analog or proportional signals.One important distinction of analog signals compared to digital signalsis that analog signals may have continuous magnitudes which relate tomathematical operations. It is herein defined that, as excitation signalA increases in a positive direction, transmissivity increases andreflectivity decreases; thereby increasing transmitted signal F₂ 302 anddecreasing reflected signal F₃ 304 proportionally. Similarly, asexcitation signal A decreases in a negative direction, transmissivitydecreases and reflectivity increases; thereby decreasing transmittedsignal F₂ 302 and increasing reflected signal F₃ 304 proportionally.Therefore, transmitted signal F₂ 302 varies in a directly proportionalmanner with excitation signal A and reflected signal F₃ 304 varies in aninversely proportional manner with excitation signal A. Thisrelationship satisfies the mathematical multiplication and divisioncriterion. Therefore, illumination signal F₂ 302 may be the mathematicalproduct of terms A and F₁, where F₂ =A·F₁, and illumination signal F₃304 may be the mathematical quotient of terms A and F₁, where F₃ =F₁ /A.Now, the mathematical equations may be described as:

    F.sub.2 =F.sub.1 ·A                               equation (3)

    F.sub.3 =F.sub.1 /A                                        equation (4)

Reflectors or prisms or both may be provided for changing the directionof an illumination signal such as with amplifier 310 operating in areflective mode. Reflector 310 may be shown without a transmittedillumination signal to illustrate that it is merely a reflector. Also,if an amplifier is operating as a reflector, then it is not necessary toassign a designation.

Other illumination processing devices such as mirrors and prisms mayalso be used to change the direction of illumination signals.

An illumination receiver such as receivers 303 and 305 may beillumination sensitive devices including photoelectric transducers suchas photocells, phototransistors, and photoresistors and includingphotosensitive media such as film, material to be eroded by an electronbeam, or other such media.

An illumination signal such as F₃ 304 may be converted to electricalform with an illumination transducer. If receiver 305 were a transducer,it may be assigned either a logical or mathematical designation shown asB. Electrical signal B 318 may be used to perform well known electricaloperations including electrical control of one or more illuminationamplifiers. Electrical signal B is an electrical equivalent ofillumination signal F₃ 305, where B and F₃ may each be used to definethe same signal. Illumination amplifier 312 is shown with the notation Bwhich is herein intended to mean that the excitation control signal B,which is generated by receiver 305, will control amplifier 312 as ifillumination signal F₃ 304, which controls receiver 305, werecontrolling amplifier 312. Inverting and complementing of electricalsignals is well known in the electronic art such as with invertingamplifiers and complementing logical gates. Therefore receiver 305 mayprovide a -B inverted mathematical signal, or a B complemented logicalsignal in place of the B non-inverted, non-complemented signal.

A signal may be connected by notation rather than by signal lines.Amplifier 312 may be shown as controlled by electrical signal B fromreceiver 305 without showing the connection from receiver 305 toamplifier 312, but merely by using the same signal designation (B) forreceiver output signal 318 and amplifier excitation signal. Similarly,amplifier 312 may be shown as controlling illumination signal F₂ 314(where F₂ is the transmitted signal 302 from amplifier 300) withoutshowing the connection from transmitted signal F₂ 302 to the inputsignal F₂ 314. It will be obvious to those skilled in the art thatillumination signals can be routed in desired directions such as withreflectors typified by reflector 310 to satisfy this routing orconnection by notation.

A receiver such as transducer receiver 305 is intended to include or toimply the signal processing devices required for providing the desiredsignal. These implied signal processing devices may take the form ofdevices 128, 116, 201, and 222 described previously with reference toFIGS. 1 and 2 herein. Lenses may be required for illumination signalprocessing and electronic amplifiers may be required for electricalsignal processing. Such signal processing devices are well known in theart and may not be discussed herein. It is herein intended that thesignal processing devices required to make an illumination signal suchas signal 304 compatible with illumination receivers such as transducer305 be implied by the receiver such as transducer 305 and it is furtherintended that signal processing devices required to make an electricalsignal such as signal B 318 compatible with the controlled device suchas amplifier 312 and gate 319 be implied by the receiver, gate, or othercontrolled device and may not be specifically described therewith.Therefore, signals will be assumed to be compatible for simplicity ofdescription.

Illumination Computer

An illumination computer arrangement has been found to be feasible andto have particular advantages when compared to well known electroniccomputers. An illumination computer may have a very low powerrequirement, particularly where there is an available source of rawillumination. For example, a space vehicle may take particular advantageof the low power characteristic. In addition, a space vehicle may havean ample supply of raw illumination such as with sunlight or moonlight.In other embodiments, logical or mathematical functions may havesignificant advantages when implementable using illuminationcomputational devices for systems that already provide illuminationsignals such as with sun and star trackers, automotive headlightdimmers, copy machines such as the well known Zerox copy machines, andother illumination control systems.

Yet another advantage of an illumination computer is the low powerconsumption, where certain illumination amplifiers such as liquidcrystal devices may consume less than a microwatt per computationalelement.

Illumination amplifier 300 provides a basic illumination control devicefor processing illumination signals. Illumination processingarrangements will now be briefly described with reference to FIG. 3A toexemplify basic illumination computer operations. Illuminationamplifiers may be used for purposes such as for exposure and forfeedback operations, where controlled illumination signal 302 may beused to expose an illumination sensitive medium in receiver 303 andcontrolled illumination signal 304 may be used to illuminate anillumination sensitive transducer such as a photocell for generatingsignal 318.

In one embodiment, the transmissivity-reflectivity characteristic ofamplifier 300 is maintained constant, thereby causing both illuminationsignals 302 and 304 to vary proportionally with input illumination 302.Therefore, reflected illumination signal 304 will be proportional toinput illumination signal 302 and may be used for direct feedbackcontrol as described hereafter.

In another embodiment, illumination 301 is maintained constant and thetransmissivity-reflectivity characteristic of amplifier panel 300varied, thereby causing the transmitted illumination signal 302 to varydirectly with transmissivity and inversely with reflectivity and causingthe reflected illumination signal 304 to vary inversely withtransmissivity and directly with reflectivity. Therefore, illuminationsignal 302 will vary inversely with illumination 304, providingcomplement or inverse operations.

In still another embodiment, both the transmissivity-reflectivitycharacteristic of amplifier 300 and the input illumination signal 301are varied, thereby causing both output illumination signals 302 and 304to vary proportionally with input illumination signal 301 and causingone output illumination signal to vary directly with amplifier 300excitation and the other output illumination signal to vary inverselywith amplifier 300 excitation. As previously discussed, this arrangementmay provide illumination multiplier operations and illumination divideroperations. Therefore, control of transmissivity in an analog(proportional) manner will provide mathematical operations and controlof transmissivity in a digital (on or off) manner will provide logicaloperations. Other logical and mathematical operations using illuminationamplifier devices will be described hereafter.

The combination of analog illumination computational devices andillumination servo arrangements permit implicit computational servos tobe implemented, where an implicit servo incorporates a computationaloperation in a feedback loop for generating an inverse computationaloperation as will be discussed hereafter.

The combination of digital illumination logical devices and illuminationservo arrangements permit latching operations to be implemented such aswith flip-flop devices and other digital memory devices as will bedescribed in detail hereafter.

The preceeding discussion develops the arrangements necessary formathematical and logical operations, which can be combined to providedigital illumination computer and analog illumination computercomputational elements. From these elements, those skilled in theelectronic computer art will be able to configure digital and analogillumination computer systems using computer design techniques wellknown in the electronic computer art.

As will be discussed relative to FIG. 5 hereafter, a single illuminationamplifier 512 can be used to control a plurality of illumination signals520 and 522 as a function of a common signal C. Many forms ofillumination such as light are highly directional, where small areas ofan illumination amplifier may be committed to individual illuminationsignals which are to be controlled as a function of the state of theparticular illumination amplifier.

Digital Control Arrangements

A digital embodiment of an illumination computer will now be describedin detail.

Digital logical elements are well known in the art and are described inthe references listed hereafter. Availability of only one or two basiclogical elements permits all logical operations to be performed such asdescribed in the reference, Digital Computer Design Fundamentals by Chuin Section 3.9 on pages 112-115 and particularly in Table 3-14. Digitallogical operations will now be discussed with reference to FIG. 3.

A logical AND operation can be performed with amplifier 300 aspreviously described, where illumination input F₁ 301 is ANDed withelectronic input signal A to form illumination output F₂ =A·F₁ 302 andwhere illumination input F₁ 301 is ANDed with electronic complementinput signal A to form illumination output F₃ =A·F₁ 304.

A logical OR operation can be performed on a plurality of illuminationsignals such as signals 308 when the signals to be ORed together areincident on an illumination amplifier such as amplifier 312, where anyone of incident signals 308 may provide sufficient illumination energyto define a logical level illumination signal. Signals 308 can belogical signals generated with various logical arrangements and providedas properly incident to amplifier 312 with illumination processingdevices such as reflectors, prisms, and lenses.

A logical NOT operation can be performed on an electronic signal A withamplifier 300, where signal 302 is equal to A and signal 304 is equal toA as previously discussed. This can be shown by setting signal 301 equalto a logical "one" and substituting into equations (1) and (2) where:

    F.sub.2 =A·F.sub.1 =A·1=A

    F.sub.3 =A·F.sub.1 =A·1=A

A logical NOT operation can be performed on an illumination signal byconverting the illumination signal to an electrical signal such as withtransducer 305 converting illumination signal 304 to electronic signal B318, then performing the logical NOT operation on the electrical signalas described previously for a logical NOT operation performed on adigital electrical signal with a well known logical inverter gate.

A logical switch or multiplexor operation can be performed as shown inFIG. 3B by having a logical signal A 330 and a logical signal B 331incident on different planes of amplifier 332. When excitation signal Cis true, signal B 331 will be transmitted as signal 333, thereby formingthe term B·C for signal F₄ 333 and signal A 330 will be transmitted assignal F₅ 334, thereby forming the term A·C for signal F₅ 334. Whenexcitation signal C is false, signal A 330 will be reflected as signalF₄ 333, thereby forming the term A·C for term F₄ 333, and signal B 331will be reflected as signal F₅ 334, thereby forming the term B·C forsignal F₅ 334. Logical equations can be derived by grouping theabovementioned terms as follows:

    F.sub.4 =B·C+A·C                         equation (5)

    F.sub.5 =A·C+B·C                         equation (6)

A logical exclusive-OR operation and a logical coincidence operation maybe performed as shown in FIG. 3C; where excitation signal D to Damplifier 340 is used to form the logical complement signals of D (D andD) in illumination signal form 342 and 347 and where excitation signal Eto E amplifier 348 is used to form the logical exclusive OR andcoincidence signals of D and E 349 and 350 respectively in illuminationsignal form. To form the complement terms of D, a logical "one" orconstant illumination 341 is incident on complementing D amplifier 340.If logical term D is true, illumination 341 will be transmitted by Damplifier 340 to E amplifier 348 as signal D 342. If logical term D isfalse, illumination signal 341 will be reflected by D amplifier 340 to Eamplifier 348 as signal D 347; where reflectors 344 and 345 process theD illumination signals 343 and 346 respectively; providing the D signal347 incident on E amplifier 348 in the proper direction. E amplifier 348is arranged for operation as previously described for the logicalarrangement shown in FIG. 3B, where equations (5) and (6) may now beused to define the logical operations performed by the arrangement shownin FIG. 3C by substituting corresponding terms; D for A, D for B and Efor C as follows:

    F.sub.1 =B·C+A·C=D·E+D·E=D⊕E equation (7)

    F.sub.2 =A·C+B·C=D·E+D·E=D ○. E equation (8)

The form of equation (7) and equation (8) are well known as a logicalexclusive --OR operation ⊕ and a logical coincidence operation ○. .

Logical flip-flop operations can be performed, as illustrated hereafterby operation of an RS flip-flop 352 which will now be described withreference to FIG. 3D. Illumination amplifier 354 is controlled by the Rreset signal 370 for performing a logical OR operation as a set S signal373 and on a feedback Q signal 368 as previously described for logicalOR operations. For steady state flip-flop operation, a flip-flop may bein either the Q or the Q complement states with either the Q signal trueand the Q signal false for the Q state or the Q signal false and the Qsignal true for the Q state. A Q signal represents a latched setcondition and a Q signal represents a latched reset condition.

In this flip-flop arrangement, R amplifier 354 is excited to betransmissive for all conditions except when reset signal R 378 is truecommanding reset of flip-flop 352. It should be noted that the S setsignal 373 and the R reset signal 378 are usually false except when theflip-flop 352 is to be set with S signal 373 or reset with R signal 378.In compliance with the notation previously discussed, amplifier 354should be transmissive when reset signal R 378 is false, therebyrequiring a logical inversion operation which is performed with NANDgate 375 to generate a reset signal R 370 that is normally true.

Assuming that the flip-flop 352 is initially in the set position, the Qillumination signal 368 is true and the R amplifier 354 is transmissive;therefore causing illumination 368 to illuminate transducer 358 togenerate a true Q₃ output signal 360 for control of Q₃ amplifier 362 tobe transmissive. Amplifier 362 receives constant input illumination 364,where constant illumination is herein defined as a logical 1 or truestate signal. In the set state, Q₃ amplifier will be excited by Q₃signal 360 to transmit signal 366, which is processed by reflectors369-370 to reflect signal 366 as signals 367-368 respectively to Ramplifier 354. Therefore, with Q signal 368 true and signal R 370 true,R amplifier 354 transmits Q₁ signal 368 as Q₂ signal 356 which maintainsflip-flop 352 in a latched set condition. Flip-flop 352 will remainlatched in this set or Q state until reset by reset signal R 370 as willbe discussed hereafter.

Flip-flop 352 will be reset by the R reset signal 370 going false,generated by the R signal 378 going true, thereby making R amplifier 354reflective. When amplifier 354 becomes reflective, the Q₂ signal 356then becomes false because the Q₂ signal 356 is dependent on atransmissive R amplifier 354. A false Q₂ signal 356 causes transducer358 to generate a false Q₃ signal 360, which causes Q₃ amplifier 362 tobecome reflective, which then causes the Q signal 372 to be true and theQ₄ feedback signal 366 to be false. As a result, the Q₅ and Q₁ feedbacksignals 367 and 368 will be false, thereby unlatching the Q feedbacklatching signal. Therefore, when the R amplifier 354 again becomestransmissive, flip-flop 352 will remain latched in the reset conditionbecause the Q₁ feedback latching signal 368 is false caused by areflective feedback Q₃ amplifier 362.

Flip-flop 352 may be set by the S set signal 373 going true when the Rsignal 370 is false, thereby making the Q₂ signal 356 true bytransmitting the S signal 373 through the transmissive R amplifier 354.With the Q₂ signal 356 true, Q signals 360, 366, 367, and 368 becometrue as previously discussed, thereby latching flip-flop 352 in the setcondition. The S signal 373 can then go false, but the flip-flop 352will remain latched in the set state with all Q signals true untilreceipt of a reset R signal 370.

Flip-flop 352 has been described for operation as an asynchronous latch.Operation as a synchronous flip-flop can be provided with input set andreset signals F₆ 376 and R 378 respectively being clocked with signalsC₁ and C₃ respectively to C₁ amplifier 374 and to NAND gate 375respectively. As is well known in the logical design art, the R signal370 can only go false for resetting flip-flop 352 when the R resetsignal 378 and the C₂ clock signal become true at the ame time as inputsto NAND gate 375. Therefore, flip-flop 352 can only be reset at a C₂clock time. Similarly, the S set signal 373 can go true to set flip-flop352 only when the C₁ amplifier 374 is transmissive for transmitting theF₆ signal 376 as the S signal 373, which occurs only when the C₁ clocksignal is true.

Therefore, flip-flop 352 can operate as either an asynchronous latch or,with clock signals C₁ and C₂, can operate as a synchronous flip-flop.

Other logical operations may be implemented and other implementations ofthe above described logic operations may be provided using the abovedescribed features of the present invention.

Certain logical operations may be performed more conveniently than otherlogical operations. As is well known in the art, logical equations canbe written in many forms and, therefore can be written in a form thatoptimizes an embodiment such as by reducing the number of lessconvenient logical operations. For example, it may be desired tominimize complement terms, which can be accomplished by manipulation oflogical equations with well known techniques such as De Morgan'stheorems.

The preceeding description has illustrated how logical operations may beimplemented with illumination devices. Because of the analogy betweenillumination logic elements and electronic logic elements and becausethe illumination logic elements satisfy Boolian equations, Boolianarithmetic, and other such well known digital design techniques; nowillumination logic elements of the present invention may be used toimplement more complex computer arrangements such as those implementablewith electronic devices and which are well known in the art.

Other digital logic devices and digital arrangements to form digitalcomputers using illumination control devices will now become obvious tothose skilled in the art from the teachings of this invention.

Analog Control Arrangements

An analog embodiment of an illumination computer has been brieflydescribed previously and will now be described in detail. For analogoperations, it will be assumed that illumination amplifiers arecontrolled to be variable transmitters or variable reflectors incontrast to the digital illumination amplifier arrangements. Analogcontrol previously described herein may be achieved with analogamplitude excitation, pulse duty cycle excitation, or other analog formsof excitation. The pulse duty cycle arrangement provides a preferredembodiment for use with this analog computer arrangement.

Constants of proportionality defined as k parameters may be used hereinto permit equations to be written in simple form without the need todefine illumination and electrical units, scale factors, and transferfunctions.

Electronic analog computational elements are well known in the computerart and are described in the references listed hereafter. Availabilityof a set of basic analog illumination computational elements permitsmore complex illumination computational elements to be built up. Forexample, multiplication elements may be used to form an exponentialcomputational element and exponential elements in an implicit servoarrangement may be used to form a root computational element as will bediscussed in detail hereafter.

Analog computational operations will now be described with reference toFIG. 3.

Analog multiplication operations may be performed with illuminationamplifier 300 as discussed previously. For amplifier A 300,transmissivity may be directly proportional to the magnitude ofelectrical control signal A; where transmitted signal F₂ 302 will bedirectly proportional to the incident signal F₁ 301 and further directlyproportional to the transmissivity which is directly proportional tocontrol signal A. Therefore, the F₂ signal 302 is directly proportionalto both F₁ and A signals and, in equation form, may be written as:

    F.sub.2 =k·F.sub.1 ·A                    equation (9)

This equation defines a mathematical multiplication operation.

Analog division operations may also be performed with illuminationamplifier 300. For amplifier A 300, reflectivity is inverselyproportional to the electrical control signal A and, therefore, thereflected signal F₃ 304 is directly proportional to the incident signalF₁ 301 and is inversely proportional to the reflectivity and, therefore,is inversely proportional to control signal A. Therefore, the F₃ signal304 is directly proportional to the F₁ signal 301 and inverselyproportional to excitation signal A and, in equation form, may bewritten as:

    F.sub.3 =[(k·F.sub.1)/A]                          equation (10)

This equation defines a mathematical division operation.

An analog addition operation may be performed on a plurality ofillumination signals such as signals 308 when the signals 308 areincident on an illumination amplifier such as amplifier 312; therebyproviding output illumination 316 and 320 proportional to the sum of theinput illumination signals 308. The analog addition operation is similarto the logical OR operation discussed previously relative to thecombination of a plurality of illumination signals.

Combined addition and multiplication or addition and division operationsmay be provided with the arrangement illustrated in FIG. 3A. Aspreviously discussed, signals 308 are added with amplifier B 312 toprovide a sum input signal Σ. As excitation signal B is varied, then thesum input signal Σ is multiplied by excitation signal B to provide aproduct output signal F₅ 320, which may be defined in equation form as:

    F.sub.5 =k·Σ·B                     equation (11)

Also, as excitation signal B is varied, then the sum input signal Σ isdivided by excitation signal B to provide a quotient output signal F₁316, which may be defined in equation form as:

    F.sub.1 =[(k·Σ)/B]                          equation (12)

Further considering input signal F₂ 314, as excitation signal B isvaried the F₂ input signal 314 will be multiplied by the B term as acomponent of the F₁ term and will be divided by the B term as acomponent of the F₅ term. These additional component terms will causeequations (11) and (12) to be written as equations (13) and (14)respectively, as will be obvious from the preceeding discussion.

    F.sub.5 =k.sub.1 ·Σ·B+[(k.sub.2 ·F.sub.2)/B]                                     equation (13)

    F.sub.1 =[(k.sub.1 ·Σ)/B]+k.sub.2 ·F.sub.2 ·B                                               equation (14)

Analog exponential operations may be illustrated with respect to FIG.3E. Input illumination signal F₇ is incident on amplifier 380 and ismultiplied by excitation signal D to form output signal F₈, where signalF₈ is equal to:

    F.sub.8 =F.sub.7 ·D                               equation (13)

Signal F₈ is incident on amplifier 381 to be multiplied again byparameter D to form signal F₉, where signal F₉ is equal to:

    F.sub.9 =F.sub.8 ·D=(F.sub.7 ·D)·D=F.sub.7 ·D.sup.2                                         equation (14)

Therefore signal F₉ is proportional to a second order term. It will nowbe obvious that higher order exponentials may also be formed by furthercascading of product terms.

An analog square root operation may be implemented as an implicit servoas will now be discussed with reference to FIG. 3F. An implicit servoperforms an analog operation (square for this example) in the feedbackof an amplifier such as amplifier 382 to generate an inverse operation(square root for this example). Input signal 383 is provided to squareroot circuits 394 which are arranged to generate the square root of aninput signal 383. Assuming that signal 383 is D², it is desired to findthe value of D. Input signal 383 is compared with feedback signal 384 inan electrode analog subtractor 382 to provide difference signal D 385.Signal 385 is then squared with amplifiers 387 and 389 as previouslydiscussed with reference to FIG. 3E. Electrical Signal D 385 ismultiplied by a constant or unity illumination signal 386 with amplifier387 to provide illumination signal D 388. Illumination signal D 388 isfurther multiplied by signal D 385 with amplifier 389 to provide signalD² 390 which illuminates transducer 391 to generate electrical feedbacksignal 384. Therefore, signal D 385 must be the square root of signalD.sup. 2 384 because of squaring computation performed with amplifiers387 and 389 and, when feedback signal 384 is servoed to be equal toinput signal 383, signal D 385 must also be the square root of signal D²383.

Square root device 394 is an implicit servo loop, with device 382 beinga summing junction. Therefore, implicit servo 394 will adjust signal D385 until signal D² 384 is equal to the input signal 383. Because signal385 is the square root (D) of feedback signal D² 384 and because signals383 and 384 are substantially equal because of closed loop servooperation, signal 385 is also the square root (D) of input signal 383.Square root computational solution is available as an electrical signal385 and as an illumination signal 388. This square root arrangement isexemplary of an implicit servo, which may be used to perform otherinverse operations by placing the other analog computationalarrangements in the feedback path of the servo.

Other analog computational devices and arrangements to form analogcomputers will now become obvious to those skilled in the art from theteachings of this invention.

It will be obvious that the arrangements shown in FIG. 3 illustratespecific embodiments of the system illustrated in FIG. 1 whereillumination amplifier devices 104 may include amplifiers 300, 312, 332and 340; where transducer devices 134 may include transducers 305, 358,and 391; where controlled illumination signals 106 may includecontrolled illumination signals 302, 304, 333, 334, 356, and 390; wherecommand signals 133 may include signals 378 and 383; and where otherdevices and signals of FIG. 1 may provide a generalized systemincorporating the arrangements illustrated in FIG. 3.

Batch Fabricated Arrangement

In accordance with another feature of this invention, a batch fabricatedillumination control device will be described for use as an illuminationcomputer. It will become obvious to those skilled in the art that thisbatch fabricated computer device is merely exemplary of features of thisinvention which may be applied to general illumination systemarrangements.

Batch fabricated electronic devices such as integrated circuits are wellknown in the art. It has been found that significant advantages can beprovided with batch fabricated illumination processing devices such asillumination amplifiers, reflectors, and transducers; where theseadvantages may be similar to the well known advantages of batchfabricated electronic circuits. In a preferred embodiment, batchfabricated illumination processing devices may be used in conjunctionwith batch fabricated electronic devices to provide substantially abatch fabricated system. Batch fabrication is herein intended to mean anarrangement that is fabricated as a composite device and may includemonolithic devices and devices where a plurality of individualoperations are provided with devices that are fabricated together as aninseparable assembly.

Illumination control arrangements may be comprised of batch fabricatedillumination amplifiers 402, 403, 434, 435 and batch fabricatedtransducers 404 as shown in batch fabricated arrangement 400, which willnow be described with reference to FIG. 4.

Illumination processing devices 402, 403, 434, 435 are shown as aplurality of diagonal surfaces such as surfaces 431-433, 455-458, and440 representing illumination amplifiers. Devices 402, 403, 434, 435 maybe constructed of glass that is molded and ground and having liquidcrystal material contained on control surfaces such as surfaces 431-433and 455-458 with etched electrodes and conductors. Other materials andprocesses will become obvious to those skilled in the art.

Although devices 402, 403, 434, 435 are shown with correspondingsurfaces aligned such as corresponding surfaces 431 and 432, differentmixes of surfaces of various configurations, orientations, andarrangements may be provided as required for the particularcomputational operations. Also surfaces may be lined up forcorresponding devices to physically mate as shown with devices 402 and434 at interface 436 or may be lined up in a manner that precludesphysical mating as shown with devices 402 and 403.

In one embodiment, batch fabricated device 434 may be arranged to matewith batch fabricated device 402 at interface 436. In such anarrangement, illumination amplifier construction may be provided withinintervals 436 such as by filling interface voids with liquid crystalmaterial and providing electrodes and conductors on interface surfacessuch as with well known etching and deposition or plating processes.Such a batch fabricated arrangement may be used to batch fabricate thecamera system discussed with reference to FIGS. 8 and 9 hereinafter suchas by filling the interface voids between lens elements with liquidcrystal material, etc. as discussed above.

Batch fabricated transducer array 404 may be constructed with well-knownprocesses and may be similar to monolithic arrays of photo-electricdevices that are well known in the art such as used in the RL-512 arraymanufactured by Reticon Corporation in Mountain View, Calif. Individualtransducers 426 may be used to control excitation for illuminationamplifiers on devices 402, 403, 434, 435 with excitation arrangementspreviously described. Illumination signals 422 are shown incident onindividual transducers 426 of transducer array 404. Semiconductordevices may be provided in a batch fabricated form such as withwell-known photo-lithographic processes using masking and depositiontechniques that are well known in the art.

One embodiment illustrated in FIG. 4 is shown as a small portion of abatch fabricated computer arrangement in two dimensional form forsimplicity of discussion. It will become obvious to those skilled in theart that the illustrated embodiment is expandable in the illustrated twodimensions and that a third dimension may be included for a threedimensional illumination computer arrangement.

Illumination signals 450-453 are incident on amplifiers 455-458respectively which may have controlled transmissivity-reflectivitycharacteristics and may generate both reflected illumination 460-463respectively and transmitted illumination 465-468 respectively undercontrol of electrical excitation. Illumination signals 470, 468 areincident on amplifiers 475, 476 respectively which may be controlled tobe only transmissive and illumination signals 418, 419 are incident onamplifiers 480, 481 respectively that may be controlled to be onlyreflective. Amplifiers controlled to be only transmissive and onlyreflective may be provided for directing illumination to the desiredillumination processing devices and illumination receivers.

Illumination signals may be transmitted in batch fabricated devices 402,403, 434, 435; which may be constructed of transmitting media such asglass or quartz; as signals 421 and may also be transmitted betweenbatch fabricated devices 402, 403 as signals 420.

It will become obvious to those skilled in the art that digital logicand analog computational operations previously discussed can beperformed with batch fabricated arrangements 400 as shown in FIG. 4.

A batch fabricated computer may be constructed in miniature form. Thehighly directly nature of many forms of illumination such as light andparticularly monochromatic coherent light such as generated by a laserpermits high intensity thin illumination beams to be processed. The highfrequency nature of many forms of illumination such as light permitsprocessing with small dimensional devices without concern with waveeffects such as standing waves, gratings, fringe patterns, and otherwell known effects involving wavelength dimensioned signal processingdevices with dimensions approaching the wavelength of the illumination.

The technology for molding, grinding, and other fabrication operationsis advanced to the state where devices such as amplifiers 431-433 mayhave dimensions of small fractions of an inch which may be less than atenth inch. The technology in transducer arrays such as constructed withmonolithic processes permits transducer arrays 404 such asphoto-electric transducer arrays to be provided with dimensions of smallfractions of an inch which may be less than a tenth inch.

In consideration of the above size discussion, batch fabricated computerdevices may be constructable with dimensions of less than a tenth inchon a side. Assuming a three dimensional arrangement having elements of atenth inch dimensions, an element will occupy a thousandth of a cubicinch. This relates to a density of one thousand elements per cubic inchor more than a million elements per cubic foot.

Power consumption can be calculated based upon the assumption of 0.1micro-ampere at 15 volts for each tenth inch square liquid crystalelement, relating to 1.5 microwatts per liquid crystal element or 1.5milliwatts per thousand elements in a cubic inch. A power density of 1.5milliwatts per cubic inch is a very low power density for powerdissipation compared to electronic computers. Power consumption of 1.5microwatts per element is approximately one thousandth of the powerconsumption of well known electronic integrated circuit logic elements.Power consumption of excitation amplifiers for exciting illuminationamplifiers may significantly exceed power consumption of theillumination amplifiers. Therefore, it should be noted that the abovepower consumption comparison will be slightly degraded for illuminationamplifiers when excitation amplifier power consumption is considered.

It will be obvious that the arrangement shown in FIG. 4 illustrates aspecific embodiment of the system illustrated in FIG. 1, whereillumination amplifier devices 104 may include batch fabricatedassemblies 402, 403, 434, and 435, where transducer devices 134 mayinclude batch fabricated transducer assembly 404; and where controlledillumination signals 106 may include controlled illumination signals420-422.

Other batch fabricated arrangements will now become obvious to thoseskilled in the art from the teachings of this invention.

Closed Loop Control

In accordance with another feature of this invention, a closed loopillumination control system will be described for providing preciseillumination control. Advantages of closed loop controls are well knownin the art and include reduction of error mechanisms within the loop,compensation for control of dynamic response and other such advantages.Although many of the features of this invention may be described withopen loop controls for simplicity herein, it is intended that thisclosed loop control arrangement be useable with each of those featuresin the various embodiments described herein.

A closed loop illumination control arrangement 508 is illustrated inFIG. 5. Illumination 510 is controlled with amplifier 512 to generatecontrolled illumination 514, 521, and 523. Transducer 134 generatesfeedback signal 114 which is processed with signal processor 118 togenerate processed feedback signal 120 for control of amplifier 512.

The servo control of FIG. 1 is shown in more detail in FIG. 5, whereincident illumination 510 is controlled by amplifier 512 for providingcontrolled illumination 514 to transducer 134. Transducer 134 generatesfeedback signal 114 to feedback signal processor 118, which generatesfeedback control signal 120 to summing junction 238. Summing junction238 compares command signal 126 and feedback signal 120 to generate aservo control signal 236A for controlling amplifier 512. Control signal236A may be related to the difference between the command signal 126 andthe feedback signal 120 and, in a preferred embodiment, is a pulsemodulated signal generated with an arrangement as previously describedin relation to FIG. 2C.

Servo 508 will control illumination 514 to be approximately proportionalto command signal 126 relatively independent of non-linearities in theservo components such as the response of amplifier 512, which may have anon-linear transmissivity with respect to excitation magnitude or othernon-linear characteristics. Servo control of illumination permitsprecise illumination signals to be generated with low level electricalsignals.

Illumination signals may be precisely directed to particular areas of anillumination amplifier, permitting an illumination amplifier to controla plurality of independent illumination signals such as amplifier 512controlling signals 510, 520, and 522. An embodiment will be discussedhereafter where a servo control signal 236A may be used to controlamplifier 512 for indirect control of other signals 520 and 522.

In one embodiment; if illumination 510 is maintained constant, thetransmissivity characteristic of amplifier 512 will be controlled byservo 508 to be proportional to command signal 126, controllingillumination 514 proportional to signal 126. This capability can beutilized to precisely control amplifier transmissivity with a constantcontrol illumination signal 510 for precisely controlling variableillumination signals 520 and 522. Assuming signal 510 is constant,assuming signal A 520 and signal B 522 are variables and assumingcommand signal 126 is a variable C; then the transmissivity of amplifier512 will be controlled by servo loop 508 to be proportional to signal Cas discussed previously. Also, as previously discussed, amplifier 512will operate as a multiplier, where transmitted signals 521 and 523,corresponding to input signals A 520 and B 522 respectively, will beproportional to mathematical products A·C and B·C respectively. Alsoamplifier 512 will operate as a divider where reflected signals 524 and525, corresponding to signals A 520 and B 522 respectively, will beproportional to the quotients A/C and B/C respectively. Therefore, itcan be seen how a servo loop 508 can control an illumination amplifier512 using an illumination control signal 510 to indirectly controlvariable illumination signals 520 and 522.

It will be obvious that the servo arrangement in FIG. 5 illustrates aspecific embodiment of the system illustrated in FIG. 1 whereillumination amplifier devices 104 may include illumination amplifier512, and where command signal processor 128 may include summing junction238, and where processed command signal 133 may include signal 236 A.

In one embodiment, summing junction 516 may include a pulse modulationarrangement such as pulse width modulator 222 to generate excitationsignal ε 236A in pulse width form. One example of this arrangement isillustrated in simplified schematic form in FIG. 2C, where negatedfeedback signal-F 120 is summed with command signal C 126 using summingresistors 237 to form an analog amplitude signal 235A. Ramp signal 233is compared with excitation signal 235A, using comparator 234A to formpulse width modulated excitation signal 236A for exciting illuminationamplifier ε 512. Other embodiments will become obvious to those skilledin the art.

Although the servo arrangement shown in FIG. 5 has been discussed forcontrol of illumination amplifier 512 in arrangement 104, it will beobvious to those skilled in the art that such a servo arrangement may beused to control an illumination source 100 with illumination amplifierfeedback and command signals 120 and 133 respectively are replaced withillumination source feedback and command signals 124 and 132respectively and where an electronic amplifier may be used to provide ahigher power signal 236A for source excitation. Also, a pulse modulationarrangement such as pulse width modulator 222 may also be used withsumming junction 238 for pulse modulation excitation of an illuminationsource.

Other closed loop excitation arrangements will be described hereafter toexemplify other forms of practicing this inventive feature relating toclosed loop excitation arrangements.

A preferred embodiment of a servo control system is described in thecopending patent applications referenced above.

In the prior art it is generally considered that liquid crystal devicesare digital (on-off) devices and are not controllable in an analog(proportional) manner. This invention provides an arrangement usingpulse modulated control signals for controlling digital (on-off) deviceswith duty cycle proportional control. Further, a servo arrangement isdescribed for providing precise analog control of such liquid crystaldevices. It will become obvious to those skilled in the art from theteachings of this invention that other devices may be controlled withpulse modulated signals or with servo arrangements and, in a preferredembodiment, with a combination of pulse modulation and servoarrangements as described in detail herein. This arrangement forcontrolling substantially uncontrollable devices such as digital devicesin an analog manner has very broad applicability such as with control ofdigital devices, mechanical devices, and other devices that will nowbecome obvious to those skilled in the art.

Flat Plane Configuration

In accordance with another feature of this invention, a flat planeintegral arrangement is provided that may include an illuminationsource, an illumination amplifier, a display overlay for legends, and aswitch panel. These devices may be used in various combinations forproviding displays, illuminated switches and other such devices.

A flat plane configuration of illumination amplifiers such as the liquidcrystal devices permit batch fabricated multi-function devices to beprovided. These multi-function devices may take the form of batchfabricated, integrated, or composite devices including an integralillumination amplifier and an illumination source and may furtherinclude integral flat plane switches and other devices. It has beenfound that such a flat plane integral arrangement provides particularadvantages such as low cost, high reliability, low volume, flexibility,and other advantages.

A self illuminated flat plane device 600 for providing controlledillumination can be configured from a composite of an illuminationamplifier 104 and illumination source 100 as shown in FIG. 6A. Theillumination amplifier 104 may be a liquid crystal device. Theillumination source 100 may be well known devices such as anelectro-luminescent panel, an illuminated diffuser panel such as groundglass panels or lucite panels which may be edge lighted or back lighted,or other flat plane illumination sources. The construction and theexcitation of such flat plane illumination sources are well known in theart and will not be discussed herein.

As shown in FIGS. 1 and 6, illumination 102 from the illumination source100 is directed toward the illumination amplifier 104 which controls thesource illumination 102 to provide the controlled illumination 106. Aplurality of illumination apertures 602-605 are provided for selectivecontrol of a plurality of illuminated areas which may be independentlyilluminated with individual illumination amplifiers 104. An illuminationmask 601 may be provided to selectively mask areas to reduce fringeillumination, to provide various aperture configurations, to isolate theareas of controlled illumination and for other such purposes. The mask601 may be a coating such as provided with painting, printing, and silkscreening processes; an overlay such as an opaque plastic device; orother well known illumination masking devices. The mask 601 may bearranged to reduce illumination outside of the areas of controlledillumination, but may not interfere with the areas of controlledillumination 602-605.

Each area 602-605 may be an independently controlled illuminationamplifier for generating controlled illumination 606-609. Illuminationsignals 606 and 608 are shown with solid lines to illustrate highintensity illumination and illumination signals 607 and 609 are shownwith broken lines to illustrate low intensity illumination.

Control and excitation devices that may be used with integralsource-amplifier device 600 have been previously discussed in detail.Control arrangements may be open loop or closed loop, analog or digital,black and white or colored, or other arrangements discussed herein.

Interface 610 between source 100 and amplifier 104 of integral device600 may be a bonded interface such as with chemical, thermal, or othertypes of bonds. As an alternate, interface 610 may be a physicalseparation between source 100 and amplifier 104 such as an air gap, withsource 100 and amplifier 104 spaced apart. An interface baffle such asthe well known "egg-crate" or other illumination masking devices may beused to mask the source illumination 102 in the spaced apart interface610. Also, brackets, standoffs, and other well known mounting fixturesmay be used to mount spaced apart illumination devices 100 and 104.

Discrete Illumination Device

In accordance with still another feature of this invention, a discreteillumination device will now be described in a display configurationwith reference to FIG. 6. In a preferred embodiment, discreteillumination device 629 provides an operator display for discreteconditions. It will be obvious to those skilled in the art that thisdisplay is merely exemplary of the features of this invention which maybe applied to discrete illumination devices in general.

In a preferred embodiment, display 620 is a flat plane display and maybe used with integral flat plane source-amplifier combination 600 forgenerating controlled illumination 106. Individually controlledapertures such as apertures 602-605 are arranged in the approximateconfiguration of an overlay or mask 622 comprising aperture masks624-630. An aperture mask may be arranged for selective transmission ofcontrolled illumination 106. Therefore, when an aperture is illuminatedwith controlled illumination 106, the related aperture mask isilluminated and the selective transmission characteristic of theparticular aperture mask will cause the corresponding aperture masksymbol to be illuminated. In a display arrangement; a first aperture 624may display the word ON, a second aperture 626 may display the word OFF,a third aperture 628 may display the word GO, and a fourth aperture 630may display the word HOLD. An unlimited number of different types ofdisplay symbols may be provided including words, letters, and othersymbols. Also, the displays masks 624-630 may be colored such as withtransparent paint to provide colored displays.

Mask symbols 624-630 may be printed, painted, or silkscreened on atransparent mask substrate or directly on amplifier panel 600 as mask601. Otherwise, mask 622 may be a film overlay or may be other wellknown mask arrangements.

A particular advantage of display 620 over prior art displays is theflexibility of generating new displays. In display 620, the integralsource-amplifier device 600 merely generates controlled illumination 106for aperture masks 624-630, where the particular aperture message isdefined by the mask 622. A change in mask 622 will change the message,which may be a simple and inexpensive change.

Broken lines 632 are used to illustrate that display 620 may be expandedfor larger display requirements.

A preferred embodiment of a discrete illumination device is arranged asan integral device and may provide an integral source-amplifier-maskcombination.

Area illumination is herein defined as controlled illumination 606-629providing substantially uniform illumination for an area such asapertures 624-630. Selective masking techniques described herein used inconjunction with controlled area illumination provides capabilities andadvantages such as low cost, small size, and flexibility over prior artarrangements.

Area illumination from a source 100 may be made uniform with well knowndiffuser arrangements. In a preferred embodiment, a diffuser may beintegrated with an illumination amplifier such as by etching orotherwise processing one of the surfaces of the glass substrates of aliquid crystal type illumination amplifier. A higher degree ofintegration may be obtained by providing an amplifier substrate as anillumination conductor such as an edge lighted device. In a preferredembodiment, an illumination conductor, diffuser, and substrate may allbe provided as a single batch fabricated assembly.

Discrete displays using incandescent bulbs are discussed herein in thecopending application Factored Data Processing System For DedicatedApplications reference above as configured for a numerical controlsystem. The flat plane display arrangement discussed is intended to beuseable for such a discrete display application.

Light Pen Arrangement

In accordance with still another feature of the invention, aninteractive control arrangement will be described providing interactiveoperator communication with illumination amplifier coding ofillumination for a light pen. It will become obvious to those skilled inthe art that this light pen arrangement is merely exemplary of moregeneral features of this invention which may be applied to generalillumination control arrangements.

A light pen is a well known input device for digital equipment and iswidely used for inputting cathode ray tube (CRT) signals. A light penconsists of a transducer for detecting a coded illumination signal andfurther consists of signal processing electronics for providing adesired input signal related to the coded illumination signal. A lightpen embodiment will now be discussed with reference to FIG. 6A. Aplurality of illumination amplifiers 602-605 are provided that generatea code with controlled illumination. Light pen 650, comprisingtransducer 134 and signal processor 138, is responsive to illuminationsignals 606-609 for generating output signal 139 related to theillumination code from a selected illumination signal 106. Transducer134 generates electrical feedback signal 114 in response to incidentillumination and signal processor 138 generates electrical output signal139 in response to input signal 114.

The light pen 650 is used by an operator who positions the light pen 650for receiving selected illumination 606-609. Because each illuminationsignal has a unique code, as will be described hereafter, output signal139 provides a coded signal that uniquely defines the operator selectedillumination.

Command device 127 and command signal processor 128 generate uniquelycoded commands 133 to each illumination amplifiers 602-605; then commandand processor devices 127, 128 receive a uniquely coded input signal 139defining the particular illumination signal selected by an operator.

It has been found that variations in ambient illumination causeunnecessary design constraints for light pen 650 and electronics 127,128. Ambient illumination may be affected by controlled illumination 106comprising illumination signals 606-609. Therefore, improved arrangementwill now be discussed for generating light pen signals which will reducevariations in ambient illumination and will provide an improvedillumination signal input for a light pen.

Waveforms shown in FIG. 6E will be used to illustrate light penoperation. Periodically, command electronics 127, 128 generates ablanking pulse 680 to turn off illumination signals 606-609.Superimposed on blanking pulse 680 are coded pulses for eachillumination signal 606-609 such as pulse duration coded signals 682,pulse position coded signals 684, and binary coded signals 686. Time isshown with arrow 681 as increasing to the right.

Pulse duration codes 682 provide code identification by the duration ofthe feedback signal 139. For example pulses 688-690 are impressed onillumination signals 606-608 respectively with amplifiers 604, 602, and603 respectively. Sensing of one of the signal 688-690 thereforeuniquely defines one of the illumination signals 606-608 respectively asselected by positioning of light pen 650 by an operator.

Pulse position codes 684 provide code identification by the timeposition of the feedback signal 139. For example, pulses 691-693 areimpressed on illumination signals 606-608 respectively with amplifiers604, 602, and 603 respectively. Sensing of one of the signal 691-693therefore uniquely defines one of the illumination signals 606-608respectively as selected by positioning of light pen 650 by an operator.

Binary pulse codes 686 provide code identification by the binary code ofthe feedback signal 139. For example, pulses 694-696 are impressed onillumination signals 606-608 respectively with amplifiers 604, 602, and603 respectively. Sensing of one of the signal 694-696 thereforeuniquely defines one of the illumination signals 606-608 respectively asselected by positioning of light pen 650 by an operator. It can beassumed that pulse 694 represents a binary one, pulse 695 represents abinary two, and therefore pulse 696 represents a binary three bybracketing pulses 694 and 695.

Codes 682-686 can be expanded to cover a large number of codes for alarge number of illumination signals, as required.

It will be obvious to those skilled in the art that blanking signal 680controls illumination for improved light pen signal processing. Also,instead of blanking pulse 680 turning-off all illumination signals606-609, blanking pulse 680 may turn-on all illumination signals,providing an alternate embodiment. This improved light pen arrangementcan also be used for CRT displays and other well known display devices.

It will be obvious that the arrangement shown in FIG. 6 illustrates aspecific embodiment of the system illustrated in FIG. 1 whereillumination amplifier devices 104 may include amplifiers 602-605, andwhere controlled illumination 106 may include illumination signals602-605.

Illuminated Switches

An illuminated switch arrangement will now be discussed using theillumination amplifier feature of this invention. In a preferredembodiment, an illuminated switch is provided in a flat plane, batchfabricated configuration, but other arrangements will become obvious tothose skilled in the art from the teachings of this invention.

Prior art, illuminated switches use mechanical toggles or latchingdevices, switch contacts, and switch mounted lamp bulbs that are excitedthrough switch contacts. The discrete devices such as mechanical latchesand switches, and the individual lamps increase size, increase expense,and decrease reliability when compared to the batch fabricatedilluminated switch arrangement of this invention.

It has been found that an illuminated switch arrangement of thisinvention provides particular advantages when used in conjunction with abatch fabricated switch arrangement such as the diaphram switch arrayPart No. DC-404 built by Datanetics Corporation of Fountain Valley,Calif. or other well-known batch fabricated switch arrangements.

As shown in FIG. 6B, a batch fabricated switch array 640 is mounted inconjunction with integral illumination assembly 620. The switch array640 may have a printed circuit board substrate 642, a spacer assembly644 with holes to define switch locations, and a conducting diaphram646. Other well known arrangements may also be used. When an operatorapplies pressure to diaphram 646 over a spacer hole location, theconductive diaphram 646 is depressed through the hole in the spacer 644to make contact with conductors on the substrate 642 to provide a switchcontact. With an illumination panel 620 having apertures such asapertures 624-630 arranged in relation to switch locations, an operatorcan depress a region on mask 622 defined by mask symbols to actuate acorresponding switch. The symbols may be located directly over theswitch locations or in close proximity with the switch locations. Thedistance required for the diaphram to move to contact the substrate maybe small, possibly only several thousandths of an inch; whereillumination panel 620 may have sufficient compliance or flexure to movethe required distance. As an alternate, the illumination panel 620 mayhave cutouts or other special areas to permit switch depression motion.

In one embodiment, memory for a momentary switch such as a batchfabricated switch can be provided with a flip-flop as will now bediscussed with reference to FIG. 2A. Flip-flop 213 may be a well knowntoggle flip-flop that is toggled when a switch is depressed with clocksignal 215. Signal 215 may be processed with well known signal processorcircuits such as for eliminating switch bounce effects. Flip-flop 213provides a memory function, where it may be toggled to an alternatestate for each switch depression, thereby providing an electronic togglememory for momentary switch operation. Flip-flop 213 may control aillumination channel 214A with select signal 212A. Therefore, each timea corresponding switch is depressed, signal 215 clocks flip-flop 213which changes state, thereby changing the state of an illuminationamplifier controlled with signal 214A.

In another embodiment, memory for a momentary switch such as a batchfabricated switch can be provided with a DC electrical storage devicesuch as a capacitor as will now be discussed with reference to FIG. 6C.Switches may be arranged as an ON switch 647 and an OFF switch 648. Whendepressed, ON switch 647 connects capacitor 649 to +V positiveexcitation 657 for charging capacitor 649 to a positive voltage. Whendepressed, OFF switch 648 connects capacitor 649 to ground GRN 658 ornegative excitation for discharging capacitor 649 to a ground ornegative voltage. Capacitor 649 provides excitation to illuminationamplifier 604 for generation of illumination 106. In this embodiment,illumination amplifier 604 may be a DC excitable device that providestransmitted illumination 106 for +V excitation and reflects illuminationfor GRD excitation. Because of the low power drain associated with manytypes of illumination amplifiers such as for liquid crystal devices,capacitor 649 may be arranged to store enough energy to excite amplifier604 for long periods of time.

In still another embodiment, the switch element may be a pressuresensitive integrated circuit element which is well known in the artpressure control systems such as devices manufactured by NationalSemiconductor Corporation Ser. No. LX 1600A. This embodiment providesparticular advantages where both, the switch element and the memoryelement, may be produced as a single monolithic device having commonintegrated circuit processes for manufacturing. Also, an integratedcircuit light emitting diodes of well known configurations may also beproduced as a part of the monolithic process and may be providedtogether with the batch fabricated switch and memory monolithic elementsfor a higher level of integration.

Other illuminated switch embodiments using illumination amplifiers,particularly batch fabricated arrangements, will now become obvious tothose skilled in the art from the teaching of this invention.

Color Control

In accordance with another feature of this invention, an electroniccontrol system for color display will be described for providingillumination of a selected color. It will become obvious to thoseskilled in the art that this color display system is merely exemplary ofmore general features of this invention which may be applied to generalillumination system arrangements. For example, color may be consideredto be only one of a plurality of spectral characteristics that may becontrolled with this arrangement. Also, light may be considered to beonly one of a plurality of illumination signals that may be controlled.

Colored light displays are in wide use such as with traffic lights,where prior art color controls are typically a plurality of illuminationsources with colored filters provided either on a bulb or on a lens forgenerating the desired colors. Color selection is performed by excitinga bulb with a mechanical switch arrangement.

An electronic control for color 650 will now be described with referenceto FIG. 6D to exemplify various arrangements for practicing thisinvention.

Unfiltered illumination 660 is incident on illumination amplifiers664-666 which are arranged to operate as color filters to transmittedillumination. This capability can be provided with many arrangementsthat will become obvious to those skilled in the art. One sucharrangement is provided by coating the output surface 678 of amplifier664 with a filter coating so that transmitted illumination 668 passingthrough the coated output surface is filtered, but reflectedillumination 678 that does not pass through the coated output surface isnot filtered. Another such arrangement can be provided by placing colorfilters 671-673 in the path of transmitted illumination 668-670.

Filtered illumination 668-670 is controlled in intensity by amplifiers664-666, where each amplifier is excited to pass an amount ofillumination related to the desired intensity of the particular color.Amplifiers 664-666 are defined for this example to have associatedfilters of red, blue, and green colors respectively which are controlledby signals R, B, and G respectively. Colored illumination 668-670 may beadded or mixed with well known illumination processing devices 679 suchas lens arrangements.

In another example, the arrangement shown in FIG. 6D may be used for awell known traffic light; where the illumination signals 668-670 maycorrespond to red, orange, and green colors respectively, where thesecolors are in common use for traffic lights. Three independent coloredlights may be provided, where each of the three illumination signals668-670 are provided as separate signals. As an alternate, all threecolors can be combined into a single light 676 for transmitting allthree colors.

Traffic lights typically provide either of three colored signals.Additional capability can be provided by providing combinations ofcolored signals simultaneously. For example, a transition from red togreen is usually made as red to orange to green. With the embodimentillustrated in FIG. 6C, combinations of colored signals can be providedsuch as a sequence of red to red-orange to orange to orange-green togreen. This sequence of colored signals may be used to alert drivers tothe portion of a change sequence in which the system is operating. Threeillumination signals can provide seven different codes plus an all zerocode for various control arrangements. As an alternate embodiment for atraffice control device, the control capability of amplifiers 664-666,permits color intensity to be changed gradually as an analog control;where, for example, the red signal 668 can decrease in intensity towardzero as the green signal 670 increases in intensity toward fullintensity to provide a gradual change from red to green conditions.

In traffic control applications, two perpendicular traffic directionsare usually controlled simultaneously with complement signals.Therefore, control of another traffic direction may be provided withreflected illumination 678 from amplifiers 664-666.

Control of Natural Illumination

In accordance with still another feature of the present invention,arrangements for control of natural illumination such as sunlight willnow be described. For simplicity, control of natural illumination willbe discussed for an inhabitable building and for an automobile usingillumination amplifier devices such as shutters, awnings, shades, andwindows. It will become obvious to those skilled in the art that theinhabitable building and automobile embodiments are exemplary of thepresent invention, where the present invention is useable for a widerange of systems including generalized structures such as residences,office buildings, and industrial buildings and further includinggeneralized vehicular systems such as aircraft, trains, and seacraft.

Control of natural illumination will be discussed herein with referenceto FIG. 7. For simplicity of discussion, only the structural form of theillumination amplifier is shown in FIG. 7, which is intended torepresent the illumination amplifier 104 shown in FIG. 1 with thevarious excitation, control, feedback and other associated arrangementsdescribed herein. These illumination amplifier arrangements may beconstructed with an illumination amplifier as an integral part of thestructural member, where for example liquid crystal material may beenclosed between panes of glass with etched electrodes, or asindependent amplifier assemblies that may be used in conjunction withseparate structural devices.

Illumination control may be provided with command signals 126 fromcommand devices 127 and feedback signals 114 from transducers 134.Command device 127 may provide manual control of illumination such aswith a potentiometer or switch or may provide automatic control ofillumination such as with a computer.

Various embodiments of devices for control of natural illumination willbe discussed in detail in the following sections entitled IlluminationControl for Buildings, Illumination Control for Vehicles, IlluminationShade, and Temperature Control.

Illumination Control For Buildings

Illumination amplifier arrangements may be arranged to control externalillumination such as sunlight to control the temperature or illuminationor both within a building. For example, electrical control of thetransmissivity of illumination amplifier window may provide precisecontrol of illumination over a range of operating conditions such asbright, direct sunlight through hazy, indirect sunlight.

Prior art illumination control arrangements are implemented asmechanical window shades, awnings, shutters and various other forms ofopaque illumination baffels. These opaque baffels may be mechanicallycontrollable such as with manually adjustable window shades or may befixed such as with many forms of shutters.

Buildings and structures are often constructed with large window areasfor style and for visibility. Shutter arrangements are often provided tolimit direct sunlight. Illumination amplifier devices in accordance withthis invention may be used for such window and shutter arrangements tocontrol transmitted illumination, thereby controlling internal lightintensity or internal temperature or both. For example, electroniccontrol of window transmissivity provides increased efficiency inillumination and temperature control of a building.

An illumination amplifier arrangement will now be described withreference to FIG. 7 for illumination control for a building. Schematicrepresentations of windows 700 and shutters 701 are shown in FIG. 7A asimplemented with illumination amplifier devices. Window panes 702 andshutters 703 may be illumination amplifiers and may be controlled eitheras a single amplifier or as a plurality of amplifiers. For example, eachwindow pane 702 of window assembly 700 and each panel 703 of shutterassembly 701 may be controllable separately or in various combinations.Also, devices such as windows 700 and shutters 701 may have panels suchas window 702 and shutter 703 partitioned into independentlycontrollable areas as will be discussed with reference to window 709with independently controllable areas 710-712 shown in FIG. 7B. Controlof amplifiers 701, 702, and 710-712 may be performed independently or invarious combinations and may be performed in digital (on-off) or analog(proportional) form and in open loop or closed loop form as discussedpreviously herein.

Control of the transmissivity of windows 702 and shutters 703 willcontrol the input illumination 704 and 705 respectively that ispermitted to be transmitted as transmitted illumination signals 706 and707 respectively. Illumination signals that are not transmitted will beassumed to be reflected as signals 717. If transmitted illumination 706,707 is permitted to be distributed within a building, transmittedsignals 706, 707 may increase ambient illumination for lightingpurposes. If transmitted illumination signals 706, 707 are permitted tobe absorbed within a building such as with an absorbtion device 708,transmitted signals may increase temperature for heating purposes.Illumination absorbtion devices may take many forms such as a blackcurtain 708, a coating on an inner surface of a window 702, or a tank ofwater 730 as will be described with reference to FIG. 7D.

Visible light transducers and temperature transducers such as transducer134 may be used to sense internal environmental conditions for controlof illumination amplifiers 702 and 703 to maintain a desired temperaturecondition, light condition, or both.

Illumination amplifiers can be applied in several forms. In oneembodiment, an illumination amplifier is constructed with a relativelythick glass substrate to be used directly as a structural panel such asa window pane. In another embodiment, illumination amplifiers may bebonded to a substrate such as a window panel to provide structuralsupport. In still a third embodiment, illumination amplifier materialsuch as liquid crystal material may be enclosed between glass substratesas with the plastic material within sagety glass panels.

Window 709 is composed of a plurality of individually controlledamplifiers 710-712. Although a plurality of amplifiers 710-712 are shownin a horizontal rectangular arrangement, it will be obvious that otherarrangements such as verticular rectangular, square, spot, and othersuch arrangements may be provided. Window 709 may be used as a sun visorfor natural illumination, as an illumination dimmer such as for controlof sunlight, and for other such purposes. Control of panels 710-712 maybe provided with illumination sensing transducers 134 or with open loopcommands from command device 127 or with both.

Arrangement 709 may be used as a sun visor where a top amplifier 712 maybe controlled for high reflectivity, a middle amplifier 711 may becontrolled for medium reflectivity, and a bottom amplifier 710 may becontrolled for low reflectivity. Amplifier 711 may be partitioned toprovide independent control of area 713 where localized illuminationtransmitted through amplifier 713 may be greater than peripheralillumination transmitted through other amplifiers 710, 712 and otherparts of amplifier 711 as will be discussed hereafter for illuminationcontrol of vehicles.

Illumination Control for Vehicles

In accordance with yet another feature of this invention, illuminationcontrol for vehicles will now be discussed for an automobile withreference to FIG. 7B.

Prior art automobile arrangements have mechanical sun visors and tintedwindows for reducing illumination. Visors may be manually controllablefor blocking illumination. Tinted windows have fixed transmissivitycharacteristics and therefore have limited capability.

Illumination amplifier arrangements provide electrical control ofillumination to meet a range of control requirements. Control of thetransmissivity of an illumination amplifier window 709 may provide moreprecise control of illumination over a range of operating conditionsincluding control of sunlight of various intensities and from variousdirections and also including control of oncomming headlightillumination occurring in a transient form.

Illumination amplifier arrangement 709 may be structured as a windshieldor other window area of an automobile and will now be discussed as awindshield to exemplify operation. Operation of arrangement 709 isfurther discussed in the embodiment of a shade in the section entitledIllumination Shade.

Amplifier 709 is shown composed of individual amplifier areas 710-712,where amplifier 711 is shown to further include individual amplifierarea 713. Incident illumination 714 may be reflected as reflectedillumination signal 715 or transmitted as transmitted illuminationsignal 716 or both reflected and transmitted as signals 715 and 716respectively. Various excitation arrangements such as digital or analogand such as open loop or closed loop have been previously discussed andare useable for this window illumination control embodiment.

All amplifier segments 710-713 of window 709 may be controlled togetheras a single amplifier arrangement for uniform control of inputillumination 714.

If illumination 714 were incident from a higher location such as fromthe sun, amplifiers 710-712 could be excited for different levels oftransmissivity; where amplifier 712 could be excited to be morereflective then amplifiers 710 and 711 for reducing the more directillumination from the sun. In a digital embodiment, amplifier 712 may beexcited to be reflective and amplifiers 710 and 711 may be excited to betransmissive to operate as a sun visor. In an analog embodiment,amplifiers 710-712 may be excited to have varying degrees ofreflectivity.

If illumination 714 were from a concentrated source such as headlightsof an oncomming vehicle or direct sunlight, reflectivity of selectedsegments could be controlled to reduce brightness and glare. Furthercontrol of such illumination may be provided with amplifier 713 whichmay be controlled to be transmissive for providing forward visibility,while other segments 710-712 may be controlled to be more reflective forreducing peripheral illumination such as from bright sunlight or fromheadlights.

As a safety precaution, a window area such as area 713 may be atransparent area without the capability for becoming reflective.Therefore, if an illumination amplifier control were to malfunctioncausing amplifiers 710-712 to become reflective and obscuringvisibility, transparent area 713 would still remain transparent fordriver visibility to bring the vehicle to a halt.

In another embodiment, arrangement 709 can be used as an anti-glaredevice such as for a rear view mirror of an automobile. Detection ofbright headlights from behind may be used to selectively controlreflectivity and transmissivity of segments 710-713 either manually orautomatically.

In still another embodiment arrangement 709 may also be used as asunvisor for a windshield of an automobile. Detection of glare, sun,headlights or other conditions can be used to selectively control thereflectivity and transmissivity of the segments either manually orautomatically.

In yet another embodiment, window 709 may be useable for other windowsof a vehicle such as a rear window or a side window. Control oftransmissivity will control illumination as described above, such as forreducing illumination from headlights of a vehicle from behind orreducing sunlight.

Amplifier 713 is exemplary of the concept of area control, where oneamplifier 713 or a plurality of such amplifier areas may be useable forselective control of illumination from particular directions. Control ofsuch amplifier areas, either manually or automatically, will provideimproved illumination control capability.

Illumination Shade

A window shade arrangement may be provided using illumination amplifiersas shown in FIG. 7B. Illumination amplifiers 710-712 may be selectivelyexcited to control input illumination 714 for providing the desiredtransmitted illumination 716 and associated reflecting illumination 715.

A window shade arrangement 709 may be used for control of sunlightentering a structure such as a home or an office by selectivelycontrolling the reflectivity and transmissivity of the segmants 710-712either manually or automatically. This window shade arrangement can bemounted in a structure such as a window, can be mounted as an awningabove a window, can be mounted as louvers outside a window, or othersuch arrangements.

Operation of an illumination amplifier shade in accordance with thisinvention will now be described with reference to FIG. 7B. Window 709 isarranged with a plurality of illumination amplifiers 710-712 of contolillumination, as previously described in the section entitledIllumination Control for Vehicles. Controlling a top amplifier such asamplifier 712 to be less transmissive than lower amplifiers 710, 711will reduce illumination from higher elevations such as sunlightincident from a high angle.

Amplifiers 710-712 may be selectively excited for controllingillumination magnitude, illumination direction, or both.

For controlling illumination magnitude, amplifiers 710-712 may becontrolled to transmit the desired magnitude of illumination, whereamplifiers 710-712 may be all controlled either together or individuallywith analog or digital control and with open loop or closed looparrangements to provide the desired magnitude of illumination 716.

In one embodiment, digital control may be selectively provided foramplifiers 710-712 to select amplifiers to be reflective and amplifiersto be transmissive. In order to control illumination 716 for a desiredmagnitude such as may be commanded with command signal 126 from commanddevice 127, signal processor 128 may switch a fixed combination ofamplifiers 710-712 to reflective states to achieve the desiredillumination magnitude. As an example, an operator controlled selectorswitch with four positions could select four conditions such as:

(1) All amplifiers transmissive

(2) Amplifiers 710 and 711 transmissive and amplifier 712 reflective

(3) Amplifier 710 transmissive and amplifiers 711 and 712 reflective

(4) All amplifiers reflective.

Other manual and automatic control arrangements may be used toselectively switch amplifiers 710-712 in a digital manner to provide thedesired illumination 716.

In another embodiment, analog control may be provided for a plurality ofamplifiers 710-712 may be excited with the same signal to control thetransmissivity of those amplifiers together to provide the desiredillumination 716. In this arrangement, amplifiers 710-712 may all becontrolled from a single command channel 235, such as from computer 251,with a single excitation signal 236 to control the transmissivity of allamplifiers 710-712 in the same manner.

In still another embodiment, analog control can be selectively provided.For reducing illumination 716; a top amplifier 712 may be controlled tobecome more reflective to limit illumination until top amplifier 712becomes fully reflective, then the next highest amplifier 711 would becontrolled to become more reflective to still further limit illuminationuntil that amplifier 711 becomes fully reflective, then the nextamplifiers in sequence would be controlled accordingly. For increasingillumination 716, the amplifiers would be controlled to become lessreflective in the reverse order, first the lowest amplifiers. Thiscapability can be provided with automatic arrangements such as byswitching between amplifiers 710-712 with threshold detectors, withservo feedback control, or with computer control. Threshold detectorssuch as comparitors 234 may be biased or otherwise controlled to switchexcitation to various operational amplifiers as a command signal 235increases in magnitude. A servo loop with feedback signal 120 to summingjunction 238 may also be used to control amplifiers 710-712 sequentiallyas will be discussed in more detail in conjunction with the aperturearrangement shown in FIGS. 8B and 8C. A computer 251 generating commandsignals 126 to signal processor 128 may also be used to controlamplifiers 710-712 sequentially.

For controlling illumination direction, amplifiers 710-712 may beselectively excited in a preferred sequence for providing directionalcontrol. Such directional control may be to reduce direct sunlight froma high angle, where the top-most amplifiers would be preferred forbecoming reflective over the lower amplifiers. Other directional controlmay be to reduce glare from a low angle, where the bottom-mostamplifiers would be preferred for becoming reflective over the upperamplifiers.

Combined direction control and magnitude control may be provided such aswith selection of a preferred sequence of amplifiers 710-712 forproviding illumination magnitude control. Such an arrangement may beunderstood with reference to the above examples, where a preferredsequence of first top amplifier 712, next middle amplifier 711, thennext bottom amplifier 710 is provided for controlling direction andmagnitude.

In order to provide a simple example of illumination control,illumination amplifier devices such as amplifier 709 may be shown withlarge, well defined segments. Other arrangements can be provided withinthe scope of this invention such as an array of segments whereinterspersed micro-segments are selectively excited to provide adistributed condition that appears as a partially reflective conditiondistributed over the controlled area. Another arrangement would provideexcitation to amplifiers 710-712 to provide partial reflectivity such aswith the analog excitation device described herein.

Other arrangements of selective control of amplifiers 710-712 arediscussed herein, in conjunction with FIGS. 7B, 8B, and 8C.

Temperature Control

A temperature control arrangement may be provided such as for a buildingwith illumination amplifier devices. One temperature control arrangementhas been discussed in the section entitled Illumination Control forBuildings with reference to FIG. 7A. Now, another temperature controlarrangement will be discussed with reference to FIG. 7D.

A tank 730 containing water 732 is exposed to sunlight 734. Anillumination amplifier 740 is used to control the transmittedillumination 738 and reflected illumination 736. Transmittedillumination 738 will heat the water 732, which may be used to heat abuilding with well known warm water heater arrangements. Illuminationamplifier 740 may be suspended above the tank 730 with supports 742 ormay be mounted directly on top of tank 730. Also, other sides of tank730 may be constructed with illumination amplifiers.

Illumination amplifier 740 may be controlled with arrangementspreviously discussed with reference to FIG. 1 such as with thermalsignals 135 and electrical signals 133. Transducer 134 may senseillumination, temperature, humidity, or other conditions and providefeedback signals 114 to signal processor 128 for control of illuminationamplifier 104 comprising amplifier 740.

The temperature control system shown in FIG. 7D may also be used forcooling with the evaporation of water 732, for distilling of water suchas salt water by collecting evaporated water with well known condensingcollecting devices, and for humidifying by evaporation of illuminatedwater.

Control of Artificial Illumination

In accordance with yet another feature of the present invention,arrangements for control of artificial illumination such as electriclights will now be described. For simplicity, control of artificalillumination will be discussed for an incandescent light bulb usingillumination amplifier devices such as shades and light bulb enclosures.It will become obvious to those skilled in the art that the incandescentlight bulb embodiment is exemplary of the present invention, but thatthe present invention is useable for a wide range of systems includingother light sources and other illumination control systems.

Control of artificial illumination will be discussed herein withreference to FIG. 7. For simplicity of discussion, only the structuralform of the illumination amplifier is shown in FIG. 7, which is intendedto represent the illumination amplifier 104 shown in FIG. 1 with thevarious excitation, control, feedback and other associated arrangementsdescribed therewith. These illumination amplifier arrangements may beconstructed with an illumination amplifier as an integral part of theillumination source as discussed with reference to FIG. 6; as anintegral part of an enclosure or structural device, where for exampleliquid crystal material may be part of a glass bulb enclosing anincandescent filament; or as independent amplifier assemblies that maybe used in conjunction with separate structural devices such as a lampshade.

Various embodiments of devices for control or artificial illuminationwill be discussed in detail in the following sections entitled LampControl, Dimmer Control, and Flasher Control.

Lamp Control

Electric lights are in wide use in virtually every inhabitable buildingand vehicle. Illumination control is universally implemented withmanually operated switches which control source excitation. In someapplications, multiple elements in a source are switched for differentillumination signal levels such as in a multiple filament bulb. Fixedlamp shades may also be used for controlling illumination direction.

An illumination amplifier arrangement for illumination control such asfor electric lights will now be discussed with reference to FIGS. 1 and7. Command device 127 generates command signals 126 as an input tosignal processor 128 for control of illumination amplifiers 104. Commanddevice 127 may be an operator control, an automatic control or otherdevice. Illumination source 100 may be excited to provide substantiallyconstant illumination and illumination amplifier 104 may be controlledsuch as with a pulse width modulator arrangement 222 previouslydescribed in reference to FIG. 2C. Illumination amplifier 104 may beconfigured as part of an enclosure for a source such as a glass bulb ormay be a separate amplifier device set apart from source 104 betweensource 104 and receiver 112. One configuration of an illuminationamplifier is shown in FIG. 7C shaped approximately as a light bulb forenclosing a light bulb as a source. Other configurations will becomeobvious to those skilled in the art from the teachings of thisinvention.

Illumination amplifiers 720 may be controlled by a digital (on-off)control or by an alalog (proportional) control for dimming capability.Amplifier 720 may be composed of a plurality of independent amplifiersshown schematically as amplifiers 721-724 for directional control andfor dimming control. Directional Control may be provided by a desiredplacement of individual amplifiers, where amplifier 721 may control thedownward illumination direction, amplifier 722 may control horizontalillumination to the right, amplifier 724 may control horizontalillumination to the left, and amplifier 723 may control upwardillumination. Control of amplifiers 721-724 for arrangement 720 may beprovided as discussed herein with reference to FIG. 7B with window 709having amplifiers 710-713. For example, amplifiers 721-724 may becontrolled in analog or digital form, in preferred sequences, and incombinations to provide either a desired illumination magnitude, or adesired illumination direction, or both a desired illumination magnitudeand direction.

Illumination 727 from a source 100 located within arrangement 720 may becontrolled by amplifiers 721-724 to be reflected internally as signal726 and transmitted as signal 725. Reflection of illumination internallymay provide illumination concentration capability for arrangement 720,where reflected illumination 726 may be concentrated through internalreflections and transmitted as illumination 725. Therefore, illuminationmay be conserved and may provide substantially constant illuminationenergy either in high intensity directed illumination or in lowerintensity distributed illumination.

In another embodiment, arrangement 720 may be mounted in a room dividerfor providing illumination to either of a plurality of rooms or forproviding lower level illumination to both of the rooms.

Dimmer Control

Electric lights are generally controlled in an on-off manner. In alimited number of prior art systems, intensity may also be controlled.Intensity is controlled in prior art systems by controlling a relativelylarge source excitation signal with potentiometer or variable inductordevices.

Prior art illumination dimmers are typified by automobile headlightdimmers which switch between multiple filaments, panel light dimmersthat decrease source excitation using a potentiometer, and room lightdimmers that decrease source excitation using a variable inductor. Thereprior art devices control source excitation and, therefore, involvecontrol of high power levels.

An illumination amplifier arrangement in accordance with the presentinvention may be provided for illumination intensity control such as forelectric lights and will now be discussed with reference to FIG. 1.Command device 127 generates command signals 126 as inputs to signalprocessor 128. Source 100 may be excited for substantially constantillumination 102 and amplifier 104 may be excited with amplifier commandsignal 133 to dim source illumination 102 by controlling reflected andtransmitted illumination 106. This arrangement provides substantialadvantages over prior art arrangements because of the low signal levelsof command signals 133 required to control source illumination 102 andthe control precision now possible with high speed amplifier devices 104and precision illumination servo arrangements.

In an automobile illumination control embodiment, a dimmer controlarrangement may be used to control automotive lights. Intensity ofheadlights, taillights and other external lights may be controlled withthe above discussed arrangement. Also, internal automobile lights suchas dash lights may be controlled with the above discussed arrangement.Further, the dimmer control arrangement may be used with a window and arear view mirror for dimming external illumination sources such assunlight or automobile headlights as prefiously discussed herein withreference to FIG. 7.

In a building illumination control embodiment, a dimmer controlarrangement may be used to control internal lighting. Intensity of roomlights may be controlled with dimmer amplifier devices arranged withlight sources as previously discussed herein in the section entitledLamp Control.

Other illumination amplifier dimmer arrangements will now become obviousto those skilled in the art from the teachings of this invention.

Flasher Control

Electric lights are generally controlled to be either in an on state oran off state. In a limited number of prior art systems, a third statemay be provided. This state is a flashing state. Flashing is controlledin prior art systems by controlling a relatively large source excitationsignal, typified by automobile turn signals. A mechanical switch may besequentially opened and closed to sequentially remove and applyexcitation to a lamp. Reliability of such a system is low because thethermal-shock of turning a lamp on and off causes degradation of thedevice. Also, relatively high power source excitiation signals must beswitched; thereby requiring more expensive power switches and causinggreater degradation of switch contacts than required with a lower powerillumination amplifier control arrangements.

An illumination amplifier arrangement will now be described forillumination flasher devices. As illustrated in FIG. 1, illuminationsource 100 generates source illumination 102. Source 100 may be a lampas in an automobile turn signal application. Illumination amplifier 104processes illumination 102 to provide controlled illumination 106.Command device 127, which may be a turn signal switch, generates commandsignal 126 to command signal processor 128 for generating flashercommand pulses 133 to illumination amplifier 104, where processor 128may include a well known astable multivibrator or other well known pulsegenerator arrangements. Command pulses 136 cause illumination amplifier104 to become alternately transmissive and reflective for eithertransmitting illumination 102 or for blocking illumination 102 frombeing output as controlled illumination 106 incident on receiver 112.Receiver 112 may be an automobile turn signal lens, a human eye, orother such receiver. Flasher command signal 133 provides relatively lowenergy excitation for illumination amplifier 104, where source 100 maybe maintained at a substantially constant illumination during flashingcoperations. Such operation reduces energy that must be switched andincreases source life as previously discussed.

Although an illumination amplifier flasher has been described as adigital (on-off) device, it can be implemented to flash betweenillumination levels other than fully on and fully off. For example, acomposite turn signal, parking light, and brake light arrangement may beprovided for an automobile; where a parking light command signal maycommand a low illumination level, a brake light command signal maycommand a high illumination level, and a turn signal flasher commandsignal may command a sequence of illumination changes between selectablehigh and low illumination levels for flasher operation. These signalscan be superimposed on each other for a composite signal.

Flexibility in controlling illumination 106 with amplifier 104 willpermit different flasher parameters to be controlled such as for flasherrate or duty cycle control. Well known arrangements such as a variablefrequency oscillator (VCO) and a reset integrator in signal processor128 may provide controlled rate flashing as commanded by command device127. A pulse width modulator arrangement such as previously discussedwith reference to FIG. 2C may provide controlled pulse width or dutycycle flashing as commanded by command devices 127.

In one embodiment, the flasher arrangement of this invention may be usedfor turn signals of an automobile as discussed above.

In another embodiment, the flasher arrangement of this invention may beused for communications. A well known communications device isimplemented with a mechanical shutter to flash an electric light. Stillanother well known communications device is provided with a mirror forreflecting sunlight toward a destination, then reflecting sunlight awayfrom the destination with mechanical motion of a mirror. An illuminationamplifier flasher arrangement in accordance with this invention providesfor flashing of an illumination signal for communications purposes.Flashing may use either reflection or transmission of the illuminationsignal to the destination, where the illumination signal may be eithersunlight, electric light, or other well know illumination signals.

In still another embodiment, the flasher arrangement of this inventionmay be used for illuminated displays. Well known display arrangementsprovide flashing capability such as for attracting an operator'sattention. An illumination amplifier flasher arrangement in accordancewith this invention provides for flashing illumination display signalfor display purposes such as for the displays discussed in reference toFIG. 6.

In yet another embodiment, the flasher arrangement of this invention maybe used for signs such as billboards, where illumination signals areflashed with illumination amplifier arrangements in accordance with thisinvention.

Other illumination amplifier flasher arrangements will now becomeobvious to those skilled in the art from the teachings of thisinvention.

As an alternate to a flasher, a varying control signal such as a rampsignal may be used to control an illumination signal , where a gradualchange in place of a step change as with a flasher may provideadvantages in many applications. A ramp signal 233 may be generated asdescribed with reference to FIG. 2C or with well known techniques suchas analog integrator arrangements.

Camera Systems

In accordance with still another feature of this invention, arrangementsfor camera systems will now be described. For simplicity, general camerasystems will be described as photographic camera systems andphotoplotter systems. It will become obvious to those skilled in the artthat these camera systems are exemplary of the present invention, butthat the present invention is useable for a wide range of systems forexposing an illumination sensitive medium, where the medium may be filmas with a photoplotter, a phosphor screen as with a cathode ray tube(CRT) and other illumination sensitive mediums.

Camera systems will be discussed with reference to FIGS. 1 and 8-10,where FIG. 1 shows a generalized embodiment of this invention and FIGS.8-10 show more specific camera embodiemnts of this invention.

Various embodiments of camera control arrangements will be discussed indetail in the following sections entitled Image Rotation Control,Aperture Control, Shutter Control, Photographic Camera System, andSource Illumination Control.

Image Rotation Control

In accordance with the camera feature of this invention, an imagerotation device is provided. This feature will herein be described for aphotoplotter system. It will become obvious to those skilled in the artthat this photoplotter system is exemplary of general features of thisinvention which may be applied to more general illumination controlsystems.

An illumination amplifier in accordance with this invention providesimage rotation control with electronic devices as an alternate to theprior art electro-mechanical devices. A photoplotter is described indetail in the previously referenced copending patent applicationsAdaptive Illumination Source Intensity Control Device. In particular, aprior art image rotation device is discussed at page 19 line 20 throughpage 21 line 6 therein.

For simplicity, the image rotation device of this invention will bedescribed with a square image rotation device having only a fewrotational positions. Additional shapes and rotational positions can beprovided and will become obvious from the teachings of this invention.Either of the complement arrangements (reflective or transmissive) canbe provided to direct the illumination in the desired direction.Further, various digital and analog command and control arrangements,some of which have been discussed herein, may be used to control thisimage rotation device.

In a photoplotter system exemplary of the image rotation feature of thisinvention, illumination 102 from source 100 is incident on illuminationamplifier 104 arranged as an image rotation device shown in FIG. 8A.Illumination 102 may be processed with various illumination processingdevices such as lenses to collimate, focus, and otherwise process theillumination.

Image rotation device 800 shown in FIG. 8A is comprised of illuminationamplifier areas 801-804 which are selectively excited to directillumination of the desired configuration. Illumination 102 from anillumination source may be collimated to illuminate the image rotationdevice 800. When segments 801-804 are selectively excited to bereflective or transmissive, illumination 102 will be selectivelytransmitted and, therefore, will selectively illuminate an illuminationsensitive medium 130 through illumination processing devices 801-804.

An example will now be presented to illustrate image rotationalcapability. For a first condition; segments 801-804 are all excited tobe reflective so that the medium 130 is not illuminated. Therefore, thisfirst all reflective condition causes the image rotation device 800 toperform as a shutter. In a second condition, segments 801 and 802 areexcited to be transmissive and segments 804 are excited to be reflectiveso that the medium 130 is illuminated in the form of a square lined upwith the axis of FIG. 8A. As a third condition, segments 801 and 804 areexcited to be transmissive and segments 802 are excited to be reflectiveso that the medium 130 is illuminated in the form of a square lined upat forty-five degrees to the axis of FIG. 8A. Conditions two and threeprovide an effective image rotation for each forty-five degree incrementof rotation. Other segment arrangements can be provided to generateother angular orientations.

Aperture Control

In accordance with the camera feature of this invention, an aperturecontrol device is provided. This feature will herein be described for aphotoplotter system and a photographic camera system. It will becomeobvious to those skilled in the art that the description is exemplary ofthe more general features of this invention which may be applied to moregeneral illumination control systems.

An illumination amplifier in accordance with this invention providesaperture control for image dimensional or size variations for aphotoplotter and exposure control for a camera using electronic devicesas an alternate to mechanical apertures used in prior art devices. Aphotoplotter is described in detail in the previously referencedcopending applications Adaptive Illumination Source Intensity ControlDevice, Adaptive Illumination Control Device, and Illumination ControlSystem referenced above showing a mechanical shutter for selectivelyexposing a medium and an aperture arrangement for controlling the sizeof the exposure image. The aperture arrangement of this invention mayprovide both shutter control and aperture size control capability.

For simplicity, square and circular image dimensional control devicesshown in Figs. 8B and 8C having only a few aperture sizes will bedescribed. Additional shapes and sizes may be provided as will becomeobvious from the teachings of this invention. Also, either of thecomplement (reflective-transmissive) arrangements may be provided asdiscussed previously

Illumination from illumination source 100 may be collimated toilluminate aperture 820 provided as amplifiers 104. When areas 826-830of aperture 820 are selectively excited to be reflective ortransmissive, input illumination 102 will selectively be transmitted asillumination 106 and, therefore, will selectively illuminate thesensitive medium 130.

An example will now be discussed relative to FIG. 8B to illustrate imagesize capability. It will become obvious that other shape apertures maybe provided, where a circular aperture shown in FIG. 8C may be used asdescribed for the square aperture of FIG. 8B, with elements 820C-830Ccorresponding to elements 820-830 respectively in the above description.For a first condition segments 826-830 are all excited to be reflectiveso that the medium 130 is not illuminated. Therefore, this first allreflective condition causes aperture 820 to perform as a shutter. In asecond condition, segment 830 is excited to be transmissive and segments826 and 828 are excited to be reflective so that the medium 130 isilluminated with the smallest image. For a third condition, segments 828and 830 are excited to be transmissive and segment 826 is excited to bereflective so that medium 130 is illuminated with a middle size image.For a fourth condition, segments 826, 828, and 830 are all excited to betransmissive so that medium 130 is illuminated with the largest sizeimage. For a fifth condition, segment 826 is excited to be transmissiveand segments 828 and 830 are excited to be reflective so that medium 130is illuminated with a "hollow" or "toroidal" type image. Such a "hollow"image has been found to have particular advantages particularly when acircular or toroidal aperture 820 is used, as will be obvious to thoseskilled in the photoplotter art. Areas or segments can be arranged togenerate apertures of other sizes and shapes and may be further arrangedto combine both, the image rotation and image dimensional controlcapabilities discussed with reference to FIGS. 8A-8C, as will becomeobvious to those skilled in the art from the teachings of thisinvention.

The aperture arrangement of this invention has been discussed usingdigital control for simplicity. It will become obvious that analogcontrol of aperture transmissivity can be provided using the teachingsof this invention either in combination with a plurality of apertures826-830 or as a single variable transmissivity aperture. A plurality ofa apertures 826-830 may be preferred because of improved illuminationcontrol. In addition, masking of the outer periphery of a lens may bedesireable when allowed by illumination considerations such as forreducing effects due to lens imperfections.

Shutter Control

In accordance with another feature of this invention, an illuminationamplifier provides electronic shutter control as an alternate to priorart mechanical shutter devices. Mechanical shutters are in wide use incamera type equipment and comprise a spring loaded mechanical bladecontrolled by an operator actuated switch.

An illumination amplifier shutter arrangement 838 will now be discussedwith reference to FIG. 8D. Input illumination 840 is incident onmechanical shutter 841 which is arranged to translate out of theillumination path as a mechanical motion shown with arrow 842 to permitillumination 840 to be incident on illumination amplifier 844 as inputillumination signal 843. Amplifier 844 may be controlled to bereflective, causing illumination 843 to be reflected as signal 845 oramplifier 844 may be controlled to be transmissive, causing illumination843 to be transmitted as signal 846. Transmitted signal 846 may beincident upon aperture 820 having reflected signal 847 and transmittedsignal 848, where a preferred embodiment of aperture 820 has beenpreviously discussed herein. Shutter amplifier 844 and apertureamplifier 820 may be combined as a single composite shutter-aperturearrangement as will become obvious to those skilled in the art, but hasbeen illustrated herein for simplicity as individual shutter andaperture amplifier devices 844 and 820.

The combination of an auxiliary shutter such as a mechanical shutter 841or other shutter device and an illumination amplifier shutter 844 haveparticular advantages. Mechanical shutter 841 may be difficult tocontrol automatically but has very low levels of illumination "leakage".Amplifier shutter 844 is easy to control automatically but may haverelatively high levels of illumination "leakage", as it may not becapable of providing a required low level of transmissivity. Therefore,use of a mechanical shutter 841 in combination with an illuminationamplifier shutter 844 provides convenient automatic illumination controltogether with low illumination leakage.

Illumination leakage through amplifier shutter 844 over long periods oftime such as hours or days may improperly expose an illuminationsensitive medium, but illumination leakage over seconds or fractions ofseconds of time may not be significant. Therefore, precise control neednot be provided with mechanical shutter 841, which may only be requiredto operate in reasonably short time periods such as seconds of time. Inprior art systems, mechanical shutters may have to operate precisely inthousandths of a second for critical exposure timing. The mechanicalshutter 841 of this invention may be a low precision, relatively slowmechanical shutter which, therefore, may be produced more economicallyand more reliably than prior art precision mechanical shutters.

In one embodiment, the shutter arrangement may be sequenced to firstopen the mechanical shutter 841, then to open the illumination amplifiershutter 844 for an exposure, then to close the illumination amplifiershutter 844 to terminate an exposure, and finally to close themechanical shutter 841 to prevent illumination leakage. Opening andclosing of the illumination amplifier shutter 844 may be preciselycontrolled to provide the desired exposure precision. Opening andclosing of the mechanical shutter 841 may be controlled with lowprecision because it's primary function may be to reduce illuminationleakage and not to control exposure period.

In accordance with the shutter feature of this invention, amplifiershutter 844 may provide precise control of illumination for exposure.Amplifier shutter 844 is controlled electrically to provide an exposureof a precise duration of time by being controlled electrically to betransmissive for exposure (shutter open) and reflective for non-exposure(shutter closed) conditions. Electrical control capability, particularlywith low excitation requirements of some illumination amplifiers, yieldsadvantages such as for providing an electronic control system for acamera or other exposure control systems.

Photographic Camera System

In accordance with still another feature of this invention, anelectronic control system for a photographic camera is provided havingillumination amplifier devices for control of photographic filmexposures. It will become obvious to those skilled in the art that thisphotographic camera system is merely illustrative of the features ofthis invention which may be applied to general illumination systemarrangements for illumination of an illumination medium.

Photographic cameras are in wide use, where prior art camera controlsare implemented with mechanical aperture, shutter, and controlarrangements.

An automatic camera control arrangement 900 will now be discussed withreference to FIG. 9.

Input illumination 901 may be incident on a partially transmissivedevice 940, which may be an illumination amplifier, for providingtransmitted illumination 910 and reflected illumination 941. Amplifier940 may be used to provide well known single lens reflex cameraoperation by directing reflected illumination 941 to a receiver 942,which may be the eye of an operator viewing an image through a viewingeye piece.

Illumination 910 may be incident on shutter-aperture arrangement 912.Arrangement 912 may include a shutter arrangement 841, 844 and anaperture arrangement 820 as previously discussed in relation to FIGS.8A-8D herein. Illumination 914 is incident on receivers 130 and 134,where receiver 130 may be an illumination sensitive medium such asphotographic film and receiver 134 may be an illumination sensitivetransducer such as a photocell. Illumination signal processing devices922 such as lenses may be used to process illumination 913 to provideprocessed illumination 914. In a preferred embodiment, devices 922 andshutter-aperture arrangement 912 may be arranged in a batch fabricatedlens, shutter, and aperture arrangement such as discussed herein. In analternate embodiment, processing devices devices 922 may include knownillumination signal processing arrangements such as lenses and filters.A partially reflective, partially transmissive illumination processingdevice 918 may be used to separate processed illumination 914 into anexposure signal which may be a transmitted signal 108 and a feedbacksignal 110. Device 918 may be an illumination amplifier, a partiallysilvered mirror, or other such device. Transducer 134 generates feedbacksignal 114 that is proportional to feedback illumination 110 and,therefore, may be proportional to illumination 914. Signal processor 128processes feedback signal 114 for generating feedback control signal 133and may also process various command signals 126 A which may include afilm sensitivity signal 934 related to film speed such as ASA or DINspeed representations, an aperture signal 935 related to apertureopering or F stop and an exposure speed signal 936 related to anexposure period. Control signal 133 controls illumination amplifierdevices 912 such as an aperture 820 and a shutter 841, 844 for providinga desired illumination signal 913 and a desired periof of time forexposing the illumination sensitive medium 130.

Exposure operations may be initiated with a mechanical operation 906such as an operator depressing a shutter switch or an automatic relayclosure. Mechanical operation 906 may close a switch in device 912 forgenerating a start expose signal 907 to signal processor 128 and mayopen an auxiliary shutter such as a mechanical shutter as previouslydiscussed with reference to FIG. 8D herein. Signal processor 128 maygenerate an exposure complete signal 908 for external control ofexposure operations.

A digital embodiment of command devices 127 and command signal processor128 will now be discussed with reference to FIG. 9B. Digital computer251 may be used to process illumination related information forgenerating command signals 126B to control illumination 910. Computer251 may be a stored program computer such as described in copendingapplication Factored Data Processing System For Dedicated Applicationsreferenced above or may be other types of digital computers which arewell known in the art. In a preferred embodiment, computer 251 has aread only memory for storage of a program as discussed in detail in saidcopending patent application. A well-known analog-to-digital (A/D)converter 138 may be used to process input signals which may includefeedback signals 114 for generating output digital signals 139 for useby computer 251. A preferred embodiment of a computer control systemwith an A/D converter and a D/A converter is described in copendingapplication Apparatus And Method For Providing Interactive AudioCommunication referenced above and incorporated herein by reference.Computer 251 may process input signals such as in response to a storedprogram and generate output digital command signals 126B to D/Aconverter 253 to control illumination devices 912 with signals 132, 133as described herein in relation to FIG. 2C. Computer 251 may process theinput signals 139 to determine the desired exposure parameters such astime of exposure, aperture amplifiers to be excited, levels ofexcitation for each aperture amplifier 826-830 and other suchparameters. Relationships between film speed, aperture transmissivity,and exposure period are well known in the photographic art and areprogrammable by computer programmers skilled in the computer art.

An analog embodiment of command devices 127 and command signalprocessors 128 will now be discussed with reference to FIG. 9C. Commandsignals 126A and 126C may be provided with well known cascadedpotentiometer arrangements shown as command devices 127. Integrator 945may start integrating command signals 126C at the start of an exposureto generate an ideal exposure ramp signal 956 related to the desiredexposure as a function of time. Simultaneously, transducer 134 may senseillumination 110 related to the start of an exposure and generateelectrical signal 114 related to illumination 110 for integration withintegrator 958 to generate an actual ramp signal 120 related to theactual exposure as a function of time. Summing junction 238 may be usedto compare the actual exposure ramp 120 with the desired exposure ramp956 to generate an error signal ε 964 for control of illuminationamplifier aperture devices such as devices 820 shown in FIG. 8B.Integrators 954 and 958 may be well known operational amplifiers such asthe Fairchild integrated circuit amplifier Ser. No. 709 and summingjunction 238 may be a well known summing resistor network and comparitorsuch as discussed with reference to FIG. 2C.

Aperture illumination amplifiers 820 may be controlled with amplifiersignal processors 128. As previously discussed in reference to FIGS. 7Band 8B, it may be desireable to control the aperture amplifiers in apreferred sequence such as first controlling the centermost amplifier836 until it is fully transmissive then controlling the other amplifiersin sequence as required to provide the desired levels of exposure.Signal processors 128 may be arranged with thresholds so that errorsignal ε 964 must exceed a fixed threshold before a particular amplifier820 will be controlled to be transmissive, where each threshold may berelated to the more preferred amplifiers 820 already being fullytransmissive and therefore requiring additional illumination from a lesspreferred amplifier. Selection of aperture amplifiers 820 is made lesscritical with the use of a closed loop servo control arrangementdiscussed previously, which will significantly reduce errors introducedwithin the servo loop as with aperture amplifier selection errors.

Shutter amplifier 844 may be controlled with control signal 970 fromsignal processor 967, which may detect when the actual exposure ramp 120reaches a desired exposure threshold, to terminate an exposure by makingshutter amplifier 844 non-transmissive. The exposure threshold may be afixed threshold or may be adjustable with input signal 968 which may bea manual potentiometer command signal. Threshold detector 967 may be anywell known devices such as a Fairchild comparitor serial no. 710 withwell known circuitry.

It will become obvious to those skilled in the art that arrangementssuch as discussed for an analog embodiment may be implemented with adigital embodiment as described previously.

The analog embodiment described above provides for a constant amount ofillumination to be generated for exposing an illumination sensitivemedium 130 as related to a single exposure such as with a photographiccamera. It will become obvious to those skilled in the art that thisarrangement is exemplary of the broad scope of illumination controlfeatures of this invention and that other arrangements may be configuredfrom the teachings of this invention. For example, a photoplotter systemmay be configured by deleting integrators 954 and 958 for controllingfeedback illumination 110 to be a constant value for a continuousexposure.

Color temperature relates to spectral response, where a blue tint is ahigh color temperature and a red tint is a low color temperature.Different films may be related to different color temperatures, whereoutdoor film emphasizes reds and indoor film emphasizes blues. Colortemperature can be controlled with arrangement 650 (FIG. 6D) includedwith shutter and aperture devices 912. Control signals 133 (FIG. 9A) maycorrespond to signals R, B, and G (FIG. 6D); input illumination 910(FIG. 9A) may correspond to input illumination 660 (FIG. 6D); and outputillumination 913 (FIG. 9A) may correspond to output illumination 668-670or 676 (FIG. 6D). Further, aperture 820 and shutter 844 may be includedin amplifiers 664-666. Control signals R, B, and G may be used tocontrol the proportion of illumination 676 each filter 671-673 transmitsand therefore control the color temperature of composite signal 676. Oneexample of the use would be to increase the proportion of redillumination 668 when indoor film is being used to take outdoor picturesby increasing the transmissivity of signal R relative to signal B.Various photographic effects can be provided with this color temperaturecontrol arrangement as will become obvious to those skilled in thephotographic art. Further, filter 673 may be a haze filter or otherspecial filter for controlling other characteristics of a photograph.Control signals R, B, and G may be provided with manual control signals126A (FIG. 9A), automatic control signals 132, 133 (FIGS. 9B and 9C) orother control signals. Further, transducer 134 (FIG. 9A) may have aspectral response matched to the spectral response of the film 130 suchas with a filter to provide a feedback signal 114 related to theintensity of a particular spectral region to which the film may besensitive.

Source Illumination Control

In accordance with yet another feature of this invention, a multiplesource arrangement is provided in conjunction with an illumination servoloop to permit operation in the presence of a source malfunction. Thisfeature will herein be described for a photoplotter system. It willbecome obvious to those skilled in the art that this photoplotter systemis exemplary of more general features of this invention which may beapplied to general illumination control systems. For example, themultiple source arrangement may exemplify an electron beam welder systemwith multiple electron sources. Further, two incandescent sources willbe described for a photoplotter system but are intended to exemplify aplurality of source elements not limited specifically to two elementsand to further exemplify a distributed or batch fabricated sourcearrangement where individual source elements may not be individuallydistinguishable. Such a multiple source arrangement may exemplify adistributed or batch fabricated source arrangement, where degradation ofa distributed source such as with degradation of illumination generatingcapability of a localized area of a source will be compensated with aservo embodiment discussed herein for two independent incandescentsources in a photoplotter system.

In accordance with still another feature of this invention, a pulsemodulated excitation arrangement is provided for proportional control ofboth, analog and digital source devices. In a preferred embodiment, apulse width modulated arrangement such as discussed in conjunction withFIG. 2C will be discussed to exemplify a general pulse modulatedexcitation arrangement.

In accordance with yet another feature of this invention, a sourceburn-out detector may be provided for improved maintainability.

A photoplotter is a well known system for exposing film to controlledlight. Typical photoplotter systems are described in patents to Gerberet al U.S. Pat. No. 3,330,182 issued in July 1967 and to Ritchie et alU.S. Pat. No. 3,323,414 issued in June 1967. Prior art systems use asingle lamp for generating light. When a lamp burns out, a prior artphotoplotter system will not operate until the lamp is replaced. If alamp burns out during operation, operation must be discontinued untilthe lamp is replaced. In prior art systems, it has not been possible toresume discontinued operation because of two primary reasons. First,lamp failure is generally accompanied with a bright flash, therebyoverexposing and ruining an artwork. Second, it has been impossible torestart operations exactly at the place where operation was interrupted.Therefore, lamp failure in prior art systems may result in loss of anartwork in process. Artwork may require many hours of exposure.Therefore, lamp burn out may result in a loss of substantial exposuretime and the associated expenses.

It has been found that an arrangement of a plurality of illuminationsources may not alone be sufficient to permit continued operation when asource burns out because the illumination signal will change inintensity due to the burned out source. It has been found further that aclosed loop illumination servo can detect a change in illumination dueto a burned out source and can automatically adjust source excitation ofa redundent source to maintain substantially constant illumination eventhrough a burn out condition. Therefore, a preferred embodiment of thisinventive feature comprises a combination of a plurality of sourceelements in combination with a closed loop illumination servo.

A closed loop illumination servo 1000 shown in FIG. 10 provides forprecision control of illumination independent of whether a plurality ofsource elements are excited or a single source element is excited andfurther provides for precision control of illumination during burn outof an element to make an automatic transition from excitation of aplurality of elements to excitation of less than that plurality ofelements. As a simplified example, a two element incandescentillumination source will be described. It will be obvious from theteachings of this invention that this arrangement is not limited to twoelements, to incandescent sources, nor to photoplotter systems. Inaddition, these source elements may be in independent enclosures such aswith two separate bulbs, may be in a single enclosure such as with amulti-filament bulb, or may be portions of a source such as areas on anillumination emitter that may become degraded but with other portionsgenerating compensating illumination. Therefore, the terms related tosources such as the multiple elements or redundant elements as usedherein are further intended to mean illumination capability exceedingthat required to generate normal illumination when they have not beendegraded in illumination generation capability, thereby permittinggeneration of the required illumination even after degradation hasoccurred.

Compensation for illumination source malfunction is provided withmultiple redundancy illumination source elements which may be multiplebulbs, multiple filaments in a single bulb or other multiple redundancedevices. When a degradation or a failure occurs in one source, theremaining source may provide the required illumination. Therefore, inthe absence of a malfunction, each of the multiple sources are operatingat partial excitation and the resultant partial illumination. As is wellknown in the art, partial excitation results in greatly extended lamplife.

In a preferred embodiment shown in FIG. 10, several incandescent lampfilaments are wired in parallel to be excited simultaneously. Anillumination servo loop 1000 provides a source excitation level requiredfor generating the commanded illumination levels. When a malfunctionoccurs in one illumination source element, the excitation level may beautomatically adjusted by servo 1000 to provide the requiredillumination 102 with only one source element.

In reference to FIG. 1, illumination source 100 may be any type ofsource well known in the art. Source 100 may be an analog sourceincluding incandescent bulbs such as tungsten, quartz, iodide, andtungsten halogen; and including solid state sources such aselectro-luminscent panels and light emitting diodes, or may be otheranalog source devices that generate illumination 102 proportional to theamplitude or duty cycle of excitation 132. Source 100 may be a digitalsource including gas tubes such as xenon lamps, flash tubes, or otherdigital source devices that operate in a digital (on-off) manner. Bothanalog and digital sources may be excited with pulse modulated digitalexcitation, where such digital excitation may be considered to be aspecial case of analog amplitude excitation comprising two amplitudeextremes, on and off, and with a duty cycle related to magnitude aspreviously discussed with reference to FIG. 2C.

Illumination source 100 is shown in FIG. 10 comprising source elements1010 and 1011 excited in parallel with excitation signal 132 forgenerating illumination signals 1012 and 1013 respectively. Illuminationsignals 1012 and 1013 may be combined into a single illumination signal102 using well known illumination processing devices 1014 such as anaccumulating lens. Illumination amplifier 1016 divides illumination 102to provide exposure illumination 108 to expose film 130 and to providefeedback illumination 110 to illuminate transducer 134. As previouslydiscussed with reference to FIG. 2C, transducer 134 generates negatedfeedback signal 120 to summing junction 238 comprising summing resistors237. Summing junction 238 sums negated feedback signal 120 fromtransducer 134 and command signal 126 from command devices 127 togenerate a processed command signal 235 related to the differencetherebetween. Processed command signal 235 is compared with ramp 233from ramp generator 239 using comparator 234 to generate pulse widthmodulated signal 132 for excitation of sources 100. Pulse widthmodulator 222 may be included in command signal processor 128 and haspreviously been discussed in detail in conjunction with FIG. 2C. When asource burns out such as source 1011 for this example, illumination 1013will reduce toward zero. Feedback sensor 134 will sense this condition,thereby causing a reduction in feedback signal 120, thereby causing anincrease in difference signal 235, thereby causing an increase in pulsewidth modulated signal 132 to excite source 1010, thereby increasingillumination 1012 to compensate for reducing illumination 1013 tomaintain illumination 102 substantially constant. Therefore, as sourceillumination 102 decreases from a level commanded by command signal 126,the servo loop 1000 will adjust excitation signal 132 to maintainsubstantially constant illumination.

In still another embodiment, a plurality of sources 1010 and 1011 may beexcited in a priority sequence, where source 1010 may initially havepriority and be excited, while source 1011 may not have priority and notbe excited for normal operation. If source 1010 were to burn out,excitation arrangement 222 may then excite source 1011 to provide thecommanded illumination. Switch-over from one source to another sourcemay be provided automatically by a servo loop with well known thresholdarrangements such as biased diodes, where burn out of lamp 1010 willcause the servo difference signal 235 to increase in magnitude undercontrol of the servo loop 1000 until the lower priority source 1011 isproperly excited.

For simplicity, the inventive feature of source redundancy has beendescribed for control of illumination 108 from redundant source 100 withexcitation signal 132. It will become obvious to those skilled in theart from this teaching that control of illumination 108 from redundantsource 100 can be controlled with amplifier 104 and excitation signal133. Therefore, compensation for source degradation can be controlledwith either source excitation signal 132 or amplifier excitation signal133 or both. Futher, redundant amplifiers may be placed in series andparallel combinations and controlled to compensate for failures to atransmissive state or reflective state respectively.

When an illumination source malfunctions, it is desireable to notify anoperator of the condition for maintenance purposes. A burn out detectormay be provided for automatic detection to notify an operator.Monitoring of source signals such as voltages, currents, impedances,temperatures, or spectrum provides information on source conditions.

When a source malfunctions, voltages and currents in a servo loop 1000may change to maintain illumination 102 constant. If source 1011 were tomalfunction, combined impedances of illumination sources 1010, 1011 mayincrease, thereby reducing current and increasing voltage of excitationsignal 132. An electrical detector 1018 may be provided to detectcurrent levels or voltage levels or both and to generate detector signal1020 to excite an anounciator 1022 to alert an operator to a burn outcondition. Announciator 1022 may be a visual announciator such as alamp, may be an audio announciator such as a buzzer or may be other wellknown announciator devices.

In another detector embodiment, separate electrical detectors may beprovided for each source 1010 and 1011 located in non-common excitationsignal lines to identify the particular source that has malfunctioned.

In still another detector embodiment, separate illumination detectorssuch as photocells may be located to sense source illumination 1012 and1013 for detecting a source malfunction.

Still a further detector embodiment would permit the operator to testthe sources by exciting and monitoring each illumination source todetect a degradation condition. This test could be performed prior tooperating the system to insure starting with a non-degraded source.

Audience Display System

In accordance with yet another feature of this invention, an audiencedisplay system will now be described. In a preferred embodiment, theaudience display system may be a large display screen such as for atheater. It will be obvious to those skilled in the art that such adisplay is merely exemplary of the teachings of this invention which maybe applied to other systems such as billboards and scoreboards.

In the prior art, audience display systems have been implemented withprojectors such as for movie theaters or with arrays of incandescentbulbs such as for scoreboards systems. Projection systems requireprojection of controlled illumination, greatly limiting intensity. Bulbarrays require control of large amounts of power and have limitedresolution. The illumination amplifier embodiment of this inventionpermits the control of high intensity illumination with low powercontrol signals and with very good resolution.

An array of illumination amplifier devices such as illustrated in FIGS.6 and 7 may be arranged to provide a display with the desired size andthe desired resolution. For example, a scoreboard that is twelve feethigh and fifty feet long having a resolution of three inches may havethree inch square illumination amplifiers arranged in an array offorty-eight amplifiers high by two hundred amplifiers long. Theseamplifiers may be arranged similar to the discrete illumination devicesdescribed with reference to FIG. 6A or in other arrangements.

In a preferred embodiment, an audience display system may be illuminatedwith floodlights either from behind for a transmissive arrangement orfrom the front for a reflective arrangement. Floodlights provide highillumination intensity levels covering a relatively large area at lowcost. Control of low power illumination amplifiers will provide controlof high levels of floodlight illumination intensity with low levelelectrical signals.

The discrete illumination device 600 of this invention shown in FIG. 6Amay be used in the audience display system. Discrete illuminationamplifiers such as amplifiers 602-605 may be implemented as relativelylarge amplifier panels arranged in an array such as for an audiencedisplay system. For the previously discussed example, each amplifiersuch as amplifiers 602-605 may be three inches square and arranged in anarray of 48 amplifiers high by 200 amplifiers long. The amount ofillumination that may be controlled may be significant, yet only lowlevel control signals would be required for this illumination amplifierarrangement. A prior art incandescent lamp scoreboard with a three inchresolution and a forty eight by two hundred feet size may be comparedwith the illumination amplifier arrangement of this invention. Assuming100 watt incandescent lamps were used for such a prior art scoreboard,10,000 lamps dissipating up to one megawatt would be required. Controlcircuitry required to switch that large amount of power would be veryexpensive. An illumination amplifier scoreboard arrangement wouldrequire significantly less power for control, possibly one millionth thepower of the incandescent lamp arrangement. Therefore, control circuitrywould be substantially reduced for the illumination amplifierarrangement.

In a preferred embodiment, a command device 127 may be used toautomatically display an image, which may be a written message, astationary picture, or a moving picture. In this embodiment, an image ofa desired display may be projected on a two dimensional array ofillumination sensitive transducers such as photo-SCRs 216 shown in FIG.2A. The array of transducers may be arranged to correspond to an arrayof illumination amplifiers so that each transducer in the array oftransducers is connected to control an illumination amplifier in acorresponding position in the array of illumination amplifiers. If atransducer 216 is illuminated with a bright illuminated portion of animage 218, a command signal 220 may be generated to cause acorresponding illumination amplifier to be excited to provide acorresponding bright illuminated point of an image for audience display.If a transducer 216 is illuminated with a dark illuminated portion of animage 218, a command signal 220 may be generated to cause acorresponding illumination amplifier to be non-excited to provide acorresponding dark illuminated point of an image for audience display.Therefore, the image projected on the transducer array will be mappedpoint for point on the illumination amplifier array for audiencedisplay. This arrangement will be discussed in more detail hereafterwith reference to FIG. 11.

A projected image may be any image including printing, handwriting,photographs, or moving pictures. Well known still picture projectors andmoving picture projectors may be used to provide the desired projectedimage.

A colored display may be provided for an audience display system byseparating colors and by controlling a colored illumination amplifierdisplay. In one embodiment, a colored image may be separated into imageseach having one of three basic colors such as well known colorseparators used in the graphic arts industry. Each of the three imagesmay be projected on a transducer array to generate three signals foreach point in an array of illumination amplifiers, each signalcorresponding to an intensity of different color component for thatdisplay point. Each of the display points may be composed of a triad ofthree illumination amplifiers such as has been described with referenceto FIG. 6D. Control of the triad of amplifiers 664-666 with acorresponding color signal will provide a color point on the display,either composed of a single illumination signal 676 or as a triad ofdifferent colored signals 668-670. A detailed example of the operationof such a colored display system will be described in detail hereafter.

An array of batch fabricated transducers 404 have been described withreference to FIG. 4 and may be used for the array of transducersdescribed for the command arrangement of the audience display system.Transducers 426 of array 404 may be digital transducers such asillumination controlled rectifiers 216 or may be analog transducers suchas photo-transistors and photo-resistors. In an analog arrangement,pulse width modulator 239 shown in FIG. 2C may be used to provide analogcontrol for an array of illumination amplifiers in response to commandsignals 235 provided by analog transducers. Therefore, an audiencedisplay system may be provided with shades of grey or shades of color.

An audience display system 1100 will now be described in detail withreference to FIG. 11. For simplicity of illustration of the operation ofthis inventive feature, only four resolution points of a two colorsystem will be described. This example is exemplary of more complexsystems and may be expanded to cover a system with three colors or morehaving resolution points of a million or more. A two colored image 1110having four resolution points 1112-1115 may have colors separated intosingle color images with each single color image 1106 and 1108 projectedon transducer arrays 1120 and 1130 respectively with well known colorseparator and projector arrangements shown as separator and projectorarrangement 1104. Transducer arrays 1120 and 1130 are then used tocontrol illumination amplifier display 1140. Resolution points 1112-1115on image 1110 correspond to illumination transducers 1122-1125respectively on a first color transducer array 1120, to illuminationtransducers 1132-1135 respectively on a second color transducer array1130, and to display amplifier pairs 1142-1145 respectively and1152-1155 respectively on display 1140. Transducer signals 1126-1129from transducers 1122-1125 respectively of transducer array 1120 exciteamplifiers 1142-1145 respectively of amplifier array 1140. Transducersignals 1136-1139 from transducers 1132-1135 respectively of transducerarray 1130 excite amplifiers 1152-1155 respectively of amplifier array1140. Individual image points 1112-1115 will now be traced through tothe final display to illustrate operation of one embodiment of thisinvention.

Image point 1112 is shown without cross hatch lines illustrative of ablank point. Blank point 1112 is separated and projected ontotransducers 1122 and 1132. Therefore, neither transducer 1122 and 1132is illuminated, providing non-exciting signals on lines 1126 and 1136resulting in neither illumination amplifier 1142 nor 1152 being excited.This excitation results in a blank display point 1142 and 1152corresponding to a blank image point 1112.

Image point 1113 is shown with a first set of cross hatch linesillustrative of a first color point. First color point 1113 is separatedand projected onto transducers 1123 and 1133. Therefore, first colortransducer 1123 is illuminated providing an exciting signal on line 1127resulting in amplifier 1143 being excited and second color transducer1133 is non-illuminated providing a non-exciting signal on line 1137resulting in amplifier 1153 being non-excited. This excitation resultsin a first color excitation for display point 1143 and 1153corresponding to a first color image point 1113.

Image point 1114 is shown with a second set of cross hatch linesillustrative of a second color point. Second color point 1114 isseparated and projected onto transducers 1124 and 1134. Therefore,second color transducer 1134 is illuminated, providing an excitingsignal on line 138 resulting in amplifier 1154 being excited and firstcolor transducer 1124 is non-illuminated providing a non-exciting signalon line 1128 resulting in amplifier 1144 being non-excited. Thisexcitation results in a second color excitation for display point 1144and 1154 corresponding to a second color image point 1114.

Image point 1115 is shown with two sets of cross hatch linesillustrative of a two colored point. Two colored point 1115 is separatedand projected onto transducers 1125 and 1135. Therefore, bothtransducers 1125 and 1135 are illuminated, providing exciting signals onlines 1129 and 1139 resulting in both illumination amplifiers 1145 and1155 being excited. This excitation results in a two colored displaypoint 1145 and 1155 corresponding to a two colored image point 1115.

Therefore, it can be seen that blank image point 1112 provides blankdisplay point 1142 and 1152, first color image point 1113 provides firstcolor display point 1143 and 1153, second color image point 1114provides second color display point 1144 and 1154, and two color imagepoint 1115 provides two color display point 1145 and 1155. It can beseen further that as colored illumination 1102 changes, points 1112-1115of illumination image 1110 will be mapped onto points 1142-1145respectively and 1152-1155 respectively of illumination display 1140 toprovide a reconstructed illumination image 1140 for display.

Other command systems for incandescent bulb type audience displaysystems are well known in the art and may be used to control theillumination amplifier audience display system of this invention.

One feature of this invention may be described as an illuminationpantograph, where a small image may be projected on a small illuminationtransducer array and be duplicated, point for point, on a largeillumination amplifier array.

Although the display arrangement of one feature of this invention hasbeen described for an audience display system, it will be obvious tothose skilled in the are that an illumination amplifier display systemmay be used for smaller display arrangements such as television displaaysystems.

Illumination Chopper, Scanner, And Modulator

The illumination amplifier feature of the present invention provides animproved means and method for chopping, scanning, and modulatingillumination. Prior art devices typically involve rotating mirrors orCRT flying spot scanners, as discussed in the articles (1) OpticalScanners; Comparisons and Applications by Compton published in theFebruary 1976 issue of Electro-Optical Systems Design and (2)Laser/Galvo Scanner Design by Tenney et al published in the October 1975issue of Electro-Optical Systems Design magazine at pages 40-45 andherein incorporated-by-reference. The illumination amplifier feature ofthe present invention can provide further advantages in combination withprior art devices. For example, the reflective surfaces used in manyprior art electro-mechanical scanners can be replaced by theillumination amplifier arrangement of the present invention to provideelectro-optical control in place of or in addition to prior artelectro-mechanical control. Still further advantages may be achievedwith a fully solid-state illumination control scanner, chopper, ormodulator device as discussed below with reference to FIGS. 12A-12C.

An illumination amplifier device is shown in FIG. 12A that may be usedas an optical scanner, chopper, or modulator. Illumination amplifiersegments 1210-1217 may be individually controlled such as to be eitherreflective or transmissive in response to electrical control signals.Illumination signal 102, shown incident upon scanner 1200, istransmitted by segments controlled to be transmissive such as withillumination 102 transmitted through segment 1210 to illuminate sensor134.

Illumination 102 may be chopped by selectively controlling segments1210-1217 to be sequentially or randomly transmissive and reflective. Asequential rotary scan will now be described for simplicity althoughother non-sequential scans may be provided. In the rotary scan, one andonly one segment is controlled to be transmissive, wherein each of thesegments is sequentially controlled to be transmissive. For example,segment 1210 may be transmissive and segments 1211-1217 may becontrolled to be reflective, then segment 1211 may be controlled to betransmissive and segments 1210 and 1212-1217 may be controlled to bereflective, then segment 1212 may be controlled to be transmissive andsegments 1210-1211 and 1213-1217 may be controlled to be reflective etcas shown in the table listing Sequential States. This table lists therepetitive sequence of scanner states and the transmissive andreflective segments for each state.

    ______________________________________    SEQUENTIAL STATES                       TRANS-    SE-     CONTROL    MISSIVE    REFLECTIVE    QUENCE  SIGNAL     SEGMENTS   SEGMENTS    ______________________________________    0       B0         1210       1211-1217    1       B1         1211       1210, 1212-1217    2       B2         1212       1210-1211, 1213-1217    3       B3         1213       1210-1212, 1214-1217    4       B4         1214       1210-1213, 1215-1217    5       B5         1215       1210-1214, 1216-1217    6       B6         1216       1210-1215, 1217    7       B7         1217       1210-1216    0       B0         1210       1211-1217    ______________________________________

After a complete scan with all segments, the scan may continuesequentially from segment 1217 to segment 1210 and repeat the sequence.This rotating scan concept is analogous to the well-known mechanicalrotating choppper used on astrotrackers such as the Kollsman KS-50astrotracker and other angular positioning devices.

A solid-state scanner will now be described with reference to FIG. 12Busing illumination amplifier devices. In the prior art, scannerarrangements use oscillating or movable mirror arrangements such as usedin the Zerox electrostatic copier machine, where a mirror is rotated oroscillated to scan a document for printing purposes. Other mechanicalscanner arrangements are well known in the art. Problems exit with suchprior scanners, where electro-mechanical scanners traverse a fixed scancycle due to inertial characteristics and where the optical output maybe "smeared" due to the continuous motion of the mechanical scanner. Asolid-state electro-optical scanner in accordance with the presentinvention provides discretely selectable conditions selectable underelectronic control independent of inertia and other such sequentialcharacteristics thereby permitting random scan arrangements andvirtually any scan sequence. Further, the scanner arrangement inaccordance with the present invention permits discrete scan position tobe selected and maintained, thereby providing a continuously changingimage to the illumination destination and minimizing the blur orsmearing effect of a continuous scan. The scanner of the presentinvention will be exemplified with a simple description to exemplify theinventive features. It is intended that this simple description beinterpreted in a broad form to include more complex scanningarrangements such as having a greater number of scan positions, usingdevices other than the liquid crystal devices, being constructed withother techniques, providing continuous scanning in contrast to discretescanning, and incorporating the various other teachings of thisinventive feature.

For simplicity, this generalized scanner concept will be discussed for amulti-layered liquid crystal embodiment although other configurationswill become obvious from the teachings thereof. A glass substrate 1222may be composed of many layers of glass at different angles 1221 allstacked and bonded together and containing liquid crystal illuminationamplifiers therebetween such as with well-known etched electrodes andliquid crystal meterial in each layer interface 1230-1237. Scanning isachieved by sequentially selecting different layers having differentreflective angles to be reflective thereby reflecting illumination to orfrom different locations. For example, if device 1224 is an illuminationsensor, scanner 1220 will sequentially detect illumination fromillumination paths 1240-1247 as the scanning progresses along path 1223.Alternately, device 1224 may be an illumination source where anillumination signals 1240-1247 may be scanned across element 1223 forselective illumination. Illumination signals from a source 1224 may befurther processed with well-known electronics. For example, illuminationsignals 1240-1247 may be accumulated with lens systems afterilluminating scanned element 1223 for processing with illuminationsensors.

In accordance with FIG. 12B, a plurality of illumination amplifierdevices may be arranged having a depth dimension into the support mediumsuch as a glass medium for liquid crystal devices, wherein theillumination must traverse transmissive illumination amplifier elementsuntil it reaches a reflective element. For example, if a first element1230 closest to the surface is reflective, illumination will bereflected in a direction 1240 determined by this surface element, and ifthe first element 1230 closest to the surface is transmissive,illumination will be transmitted to a second amplifier 1231 next closestto the surface through the first transmissive element 1230. If thesecond element 1231 is reflective, illumination will be reflected in adirection 1241 determined by this second element 1231 which is the firstreflective element, and if the second element 1231 is transmissive,illumination will be transmitted to a third amplifier 1232 next closestto the surface through the first two transmissive amplifier elements1230 and 1231 and so forth until the illumination is incident upon afirst amplifier having a reflective characteristic. This first amplifierhaving a reflective characteristic will determine the selected angle ofthe scanner. Therefore, the illumination from the source may betransmitted through a plurality of illumination amplifiers that arenon-reflective until incident upon the first illumination amplifier thatis reflective, thereby electro-optically selecting the particularscanner angle.

For simplicity of discussion, a sequential scanning arrangement ofscanner 1220 will now be discussed. For simplicity of illustration, itshall be assumed that one and only one amplifier layer 1230-1237 oflayers 1221 is controlled to be reflective and all other amplifierlayers are controlled to be transmissive although other scans may beprovided to make combinations of elements 1230-1237 reflective andtransmissive. For a sequential scan, illumination amplifier 1230 isfirst controlled to be reflective thereby generating reflectiveillumination signal 1240, then amplifier 1230 is controlled to betransmissive and amplifier 1231 is controlled to be reflective therebygenerating reflective illumination signal 1241, then amplifiers 1230 and1231 are controlled to be transmissive and amplifier 1232 is controlledto be reflective thereby generating reflective illumination signal 1242,etc. The sequential scan may proceed as shown in the table listing ScanStates. This table lists the repetitive sequence of scanner states andthe transmissive and reflective elements for each state.

    __________________________________________________________________________    SCAN STATES           CONTROL                  TRANSMISSIVE                             REFLECTIVE                                     ILLUMINATION    SEQUENCE           SIGNAL SEGMENTS   SEGMENTS                                     SIGNAL    __________________________________________________________________________    0      B0     1231-1237  1230    1240    1      B1     1230, 1232-1237                             1231    1241    2      B2     1230-1231, 1233-1237                             1232    1242    3      B3     1230-1232, 1234-1237                             1233    1243    4      B4     1230-1233, 1235-1237                             1234    1244    5      B5     1230-1234, 1236-1237                             1235    1245    6      B6     1230-1235, 1237                             1236    1246    7      B7     1230-1236  1237    1247    0      B0     1231-1237  1230    1240    __________________________________________________________________________

When the last amplifier 1227 is controlled to be reflective to generateillumination signal 1247, then scanner 1220 may be controlled to"retrace" by making amplifier 1230 again reflective and therebyretracing from signal 1247 to signal 1240 to start a new scan alongelement 1223.

An alternate embodiment is illustrated with the following Alternate ScanStates table.

    __________________________________________________________________________    ALTERNATE SCAN STATES           CONTROL                  TRANSMISSIVE                            REFLECTIVE                                    ILLUMINATION    SEQUENCE           SIGNAL SEGMENTS  SEGMENTS                                    SIGNAL    __________________________________________________________________________    0      B0     NONE      1230-1237                                    1240    1      B1     1230      1231-1237                                    1241    2      B2     1230-1231 1232-1237                                    1242    3      B3     1230-1232 1233-1237                                    1243    4      B4     1230-1233 1234-1237                                    1244    5      B5     1230-1234 1235-1237                                    1245    6      B6     1230-1235 1236-1237                                    1246    7      B7     1230-1236 1237    1247    0      B0     NONE      1230-1237                                    1240    __________________________________________________________________________

Many other alternate embodiments may be provided from the teachingsherein.

The scanner inventive feature described above may be characterized asselecting a sequence of elements having different reflective angles toselect each of a plurality of sources of illumination (or to select eachof a plurality of destinations of illumination) having different anglesof incidence (or having different angles of reflection) to providesubstantially a constant reflective angle (or incidence angle) toprovide reflected illumination to a sensor (or from a source). Othercharacterizations may include a solid-state scanning device, anelectro-optical device for scanning a plurality of sources ofillumination to provide scan illumination to a receiver, and a pluralityof illumination amplifier devices each having different angularpositions for selecting different sources of illumination for reflectingselected illumination to a receiver device.

The illumination amplifier scanner of the present invention may takemany forms, where one form is a plurality of individual discreteillumination amplifier elements arranged at different angles. Anotherform may be provided as a batch fabricated illumination amplifier asshown in FIG. 4 where a plurality of illumination amplifier surfacessuch as surfaces 440 and 457 may be sequentially selected to reflect (ortransmit) different source images to a common receiver element. Stillanother embodiment may be a planner arrangement such as illustrated inFIG. 6A, where amplifier elements 602-605 may each be provided having adifferent angle and where each may be selected in sequence to bereflective to reflect different images to a common destination element.Other scanner embodiments may be arranged as concentric squares andcircles as illustrated in FIGS. 8B and 8C, wherein each segment may bearranged at a different angular position. Other configurations may beprovided such as determined by convenient manufacturing methods toprovide a plurality of illumination amplifiers having different angularpositions therebetween in accordance with the teachings of the scannerfeature of this invention.

A multi-dimensional scanner arrangement may be provided having atwo-dimensional angular orientation between a plurality of illuminationamplifier elements. In one batch fabricated arrangement, a sphericalsurface may be provided having facets arranged about the surface of thespherical device having different orientations in two dimensions.

One optical scanner in accordance with the present invention may becharacterized as a single photosensor with a plurality of electronicallycontrolled amplifier elements each selecting a particular source ordirection for reflecting to the single photosensor. The photosensor andassociated electronics may be considered as being time-shared between aplurality of source elements selectable with the illumination amplifierelements.

The scanner feature of the present invention may be usable in the placeof present well-known scanner arrangements including the rotating mirrorassociated with a Zerox copy machine, the rotating mirror and photocellarrays associated with optical character recognition systems, a Vidiconand other tube scanners associated with television cameras, flying spotscanners, and other well-known scanning devices.

Scan control may be provided with the relatively simple counter anddecoder arrangement of FIG. 12C or may be provided with highercapability electronics such as a digital computer controlled scan. Inorder to exemplify this feature of the present invention, a simplesequential scan arrangement will be discussed with reference to FIG.12C. Sequential scanning may be controlled with binary counter 1204being repetitively sequenced through eight counts under control of clocksignal CK. The squential binary count from counter 1204 may be decodedwith decoder 1205 to generate one of eight control signals B0-B7 inresponse to the three binary encoded signals B, C, and C from counter1204. Each of the eight control lines from decoder 1205 may be used tocontrol a different amplifier segment of scanner 1200 (FIG. 2A) and adifferent amplifier level of scanner 1220 (FIG. 2B). For example,decoder output signals B0-B7 may control amplifier segments 1210-1217respectively of scanner 1200 and may control amplifiers 1230-1247respectively of scanner 1220. As counter 1204 sequences through thebinary count, decoder 1205 sequences through the eight control signalsB0-B7; wherein the selected control signal from decoder 1205 will causethe related segment of scanner 1200 to become transmissive (operating inthe transmissive mode) and will cause the related amplifier of scanner1220 to become reflective (operating in the reflective mode). Counter1204 and decoder 1205 may be well-known Texas Instruments S/N 7400integrated circuit logic wherein counter 1204 may be an S/N 7491 counterand decoder 1205 may be a S/N 7445 decoder.

For simplicity of discussion, mutually exclusive control has beendescribed where one and only one segment of scanner 1200 is controlledto be transmissive and one and only one amplifier of scanner 1220 iscontrolled to be reflective, but many other combinations can beprovided. For example, scanning may be random in nature for adaptivescanning or may be selective in nature to select a particular segment orangle without traversing a sequential scan. Further, variouscombinations of segments and amplifiers may be controlled to betransmissive or reflective.

For further simplicity of discussion, the angular dimensions andresolution of amplifier segments 1210-1217 and amplifiers 1230-1237 areshown in exaggerated form. In other embodiments, the segments of scanner1200 may have fine angular resolution such as 1024 segments being usedinstead of the eight segments of the present example. Further, theangles of amplifiers 1230-1237 of scanner 1220 may have greaterresolution such as 1024 scanning angles in place of the eight angles ofthis example. Still further, the interchangability of the reflective andtransmissive modes as discussed above permits the scanners to operate ineither the reflective or transmissive mode. For example, scanner 1200has been discussed for transmissive mode operation and scanner 1220 hasbeen discussed for reflective mode operation, where alternately scanner1200 may operate in the reflective mode and scanner 1220 may operate inthe transmissive mode.

Still further, control may be provided in analog form wherein amplifiers1210-1217 of scanner 1200 and amplifiers 1230-1237 of scanner 1220 maybe controlled to be partially reflective and partially transmissive suchas by using the pulse modulated control arrangement discussed withreference to FIG. 2.

Yet further, an analog scan may be provided by implementing continuouslyvariable controls such as discussed in U.S. Pat. No. 3,675,988 to Soref,which is herein incorporated-by-reference, thereby providing acontinuous scan in contrast to the discretely stepped scan discussedwith reference to FIGS. 12A-12C.

A closed loop adaptive scanner embodiment will now be discussed withreference to FIG. 1. Command device 127 may be an adaptive commanddevice such as a stored program digital computer or may be otherwell-known adaptive command devices. Command device 127 generatescommand signal 126 to the command signal processor 128, as previouslydiscussed with reference to FIG. 1. Control signals 133 to amplifier 104may control amplifiers 1210-1217 and amplifiers 1230-1237 (FIGS. 12A and12B), wherein these amplifier elements are included in the generalamplifier block 104. Illumination transmitted or reflected toillumination detectors as shown in FIG. 12 corresponds to illumination110 to sensor 134 (FIG. 1). Sensor signal 114 may be communicated toadaptive device 127 as signals 139 for adaptive control. Command device127 may command scanning or monitoring with a single amplifier angle andmay adaptively change the monitored angle to optimize the feedbacksignal 139. Adaptive control with feedback to a digital computer isdiscussed in applications Ser. No. 134,958 and Ser. No. 135,040 for amachine control system and are equally applicable to the illuminationcontrol system of the present invention.

A specific use of the electro-optical chopper of the present inventionwill now be discussed in detail to exemplify the more general featuresof the present invention.

Mechanical chopper arrangements are well known in the prior art such asillumination choppers used for startrackers such as the KollsmanAutomatic Astro Compass type KS-50-03. Such prior art devices provide arotating mechanical shutter that permits incident light to betransmitted or blocked as a function of the angular position of theincident light and the phase of the mechanical shutter rotation.

In accordance with the teachings of the present invention, anillumination amplifier chopper may be provided using amplifiers 104controlled by signals 133 to chop illumination 102 to generate choppedillumination 106. Amplifiers 104 may be arranged with segments having aparticular orientation, discussed with the reference to FIG. 12A.Control signals 133 select the various segments in sequence, which maybe a clockwise or counter-clockwise sequence as with the mechanicalchoppers or, in a preferred embodiment, may select the segments in arandom access sequence such as may be defined under control of commanddevices 127 which may include a computer 251.

In a preferred mode of operation, an initial acquisition scan such as acomplete clockwise scan using all segments may be performed to initiallylocate an image. After an image has been located, only segments closelyassociated with the image location may be scanned in an adaptive mannerto increase the duty cycle of the chopped signal and to decrease there-acquisition time. This adaptive capability provides significantadvantages over prior art mechanical chopper arrangements, wheremechanical choppers and other sequential devices do not provideselective or random access illumination chopping capabilities. Theelectronic control arrangement of the present invention permits externalillumination to be chopped in almost any desired random order orsequence based upon optimizing the particular system considerations.

In contrast to prior art illumination chopper systems, the system of thepresent invention provides null seeking capability with a computercontained in command devices 127 (FIGS. 1 and 9B) for commanding theselective chopping of illumination with amplifiers 104 under control ofcommand signals 126 to command signal processors 128 to generate controlsignals 133 to provide chopped illumination 106. Transducer 134generates feedback signals 114 to signal processors 116, where computer251 in command devices 127 is responsive to feedback signals 139 todetermine the location of the illumination. Computer 251 and commanddevices 127 control the system to center the illumination such as bycontrolling a gimballed startracker to reposition the image in thetelescope, as is well known in the art. Computer 251 would continuallyadjust such a controlled arrangement to center the illumination inresponse to the chopped feedback signals until incident illumination iscentered, indicative of equal feedback signals when each of theillumination amplifier segments 104 were selected by computer 251.

In one embodiment of the scanning arrangement shown in FIG. 12A, digitalcounter 1204 included in command devices 127 generates binary outputsignals 1206 included in signals 126 to decoder 1205 included in commandsignal processor 128. Decoder 1205 decodes binary inputs signals 1206 togenerate individual select output signals B0-B7 which sequentiallyselect segments 1210-1217 or 1230-1237 to chop input illumination 102 togenerate chopped output illumination 106 to illuminate transducer 134.The output of transducer 134 excites signal condition devices 116 togenerate feedback signal 139 such as by loading the output of counter1204 into the computer when the chopped signal 106 illuminatestransducer 134. Therefore, the number loaded into the computer isindicative to the segment of chopper 104 upon which illumination 102 isprojected, where the number loaded into the computer is indicative ofthe direction in which illumination 102 is off from the center 1201 ofthe chopper.

The number loaded into the computer may be used to identify theoff-center condition of illumination 102 to process information, or tocontrol the system, or both in response thereto using well-known priorart arrangements.

Chopper arrangement 1200 is shown in a simplified embodiment in FIG. 12Ato exemplify the present invention. It will become obvious from theteachings of the present invention that more sophisticated arrangementsmay be configured, where the computer may directly or indirectlygenerate select signals B0-B7 in either a sequential form as describedabove or in a random access form to select particular segments in orderto optimize system considerations.

Further, a computer may receive feedback signal 139 as a discrete inputsignal as described in the referenced copending applications to identifythe segment illuminated by illumination 102. In one embodiment, computer251 in command device 127 and command signal processor 128 may replacecounter 1204 and decoder 1205 to generate select signals B0-B7 in apreferred sequence or in a random manner and may monitor output signal139 of sensor 134 to determine the off-center direction of illumination102. In another embodiment, the computer may select a particular segment1210-1217, then monitor signal 139 to determine the illuminationcondition, ten continue to interrogate the various segments 1210-1217and, in conjunction with each interrogation, monitor signal 139 todetermine the off-center direction of illumination 102. In still anotherembodiment shown in FIG. 9B, computer 251 may receive feedback signal139 as a whole number digital signal from an analog-to-digital converter138 included in feedback signal processor 116 to define the relativeamplitude of illumination intensity.

In yet another feedback embodiment discussed with reference to FIG. 12C,sensor 134 (also shown in FIG. 12A) may receive chopped illumination 106(FIG. 12A) and may generate feedback signal 114 to C-Register 1207 toload output signals 1206 from counter 1204 into C-Register 1207 inresponse to feedback signal 114. The contents of C-Register 1207,indicative of the angular position of incident illumination 102 (FIG.12A) may be loaded into computer 251 for control of scanner 1200 and forcontrol of other system operations. Loading of C-Register 1207 andcommunication between C-Register 1207 and computer 251 is discussed inthe referenced applications, particularly in application Ser. No.291,394.

Mechanical scanners are well known in the art and interfacing thereofmay be used to interface the electrooptical scanner of the presentinvention.

A preferred arrangement for interfacing chopper 1200 with an electronicsystem such as with a computer will now be discussed with reference toFIGS. 12A and 12C. Chopping of illumination signal 102 to obtain choppedillumination signal 106 provides a phase relationship that determinesthe direction of offset of illumination 102 from being focused directlyon the center 1201 of scanner 1200. Sensor 134 generates output pulse114 when chopped illumination 106 illuminates sensor 134. This conditionoccurs when counter 1204 commands the segment that is illuminated by theoff-center illumination, which is segment 1210 in the example shown inFIG. 12A, to be transmissive thereby illuminating sensor 134 withchopped illumination 106. Therefore, the state of counter 1204 whensensor 134 detects chopped illumination 106 identifies the segmenttransmitting the chopped illumination 106 and therefore identifies thedirection oof the incident illumination 102. The mechanization shown inFIG. 12C can provide feedback to an electronic system where sensor 134generates output signal 114 when counter 1204 controls the segmenthaving the incident illumination 102 transmitted thereon to betransmissive. Therefore, sensor signal 114 (FIG. 1) may be used tocontrol loading of signals 1206 from counter 1204 into C-register 1207for storing identification of the segment related to the direction ofincident illumination 102. C-register 1207 may then be used as aninterface register between scanner 1200 and an electronic system whichmay include a computer 251 (FIGS. 2C, 9B, and 12C).

The electronic system interface may be better understood relative to thedisclosures in the referenced copending applications. For example, theC-register interface with a computer is discussed in detail inapplication Ser. No. 101,881; particularly with reference to FIG. 13therein showing C-register 260. Further, a preferred embodiment of theC-register is discussed in application Ser. No. 291,394 particularlywith reference to FIG. 7 therein. Said FIG. 7 shows C-register 460 beingloaded with input signals 708 in response to load strobes DC-7 and DC-3and the transfer of the loaded information from C-register 460 toA-register 706 in computer 112 as discussed therein, where strobe DC-7may be output signal 114 from sensor 134 discussed herein and inapplication Ser. No. 366,714. Still further, a sequence of controlsignals may be generated in response to an input signal with themechanization disclosed in application Ser. No. 302,771; particularlywith reference to FIG. 5 therein; wherein input signal 283 is processedwith digital electronics to generate a sequence of clear signal 506 andenable signal 508 which may be used to clear and load the C-register; asdiscussed above for FIG. 7 of application Ser. No. 291,394; in responseto the input signal 114 from sensor 134. Alternately, computer 251 maydirectly monitor ouput signal 114 of sensor 134 such as with askip-on-discrete instruction and may directly control transmissivity andreflectivity of segments 1210-1217 such as by using the C-registerdiscussed above as an output register.

An alternate embodiment wherein the computer is included in the feedbackloop will now be discussed with reference to FIG. 12D. Computer 251packs together a combination of one bits and zero bits in the internalA-register, wherein each packed bit corresponds to a different segment1210-1217 of scanner 1200 and wherein a one state may definetransmissivity and a zero state may control reflectivity for thecorresponding segments 1210-1217. Such operations may be performed withwell-known table lookup and packing operations. Computer 251 may thenoutput the packed discrete word from the A-register to the interfaceC-register 1207, wherein the packed discrete conditions B0-B7 are storedin C-register 1207 to control segments 1210-1217 of scanner 1200.Computer 251 packs together and outputs a new control word B0-B7 toC-register 1207 for every scan increment such as for each desired changein transmissivity and reflectivity of one or more segments 1210-1217;which may be sequential changes implemented with well-known counting,polling, and/or indexing programming methods. Incident illumination 102is conditionally transmitted or chopped by scanner 1200 to generatechopped illumination 106 to illuminate sensor 134. Sensor output signal114 may be sensed directly by computer 251 such as with askip-on-discrete instruction. Computer 251 may either sequentially scan,randomly scan, or adaptively scan illumination 102 by monitoringfeedback signal 114 to identify the direction or other characteristicsof incident illumination 102. Therefore, computer 251 in the scanningloop may reduce special purpose electronics and may provide flexibilityand adaptive control. A preferred embodiment of such a computer isdiscussed in application Ser. No. 101,881; where the preferredembodiment includes a read only memory and a scratch pad memoory in amicro-computer type configuration.

For simplicity of discussion, illumination signals between element 1224and scanner 1222 are shown at different angles indicated by signal paths1240-1247. These signals 1240-1247 inbetween scanner 1222 and generator1224 may actually be colinear, parallel, or have other suchrelationships.

A scanner embodiment may be used for display purposes, wherein thisscanner inventive feature will now be discussed with reference to FIG.12B. In this embodiment, element 1223 may be a multi-character displayand may be a frosted glass screen or other projection device and element1224 may be a character generator such as a single liquid crystalcharacter being controlled from well-known digital display electronics.Refresh electronics such as discussed in applications Ser. No. 101,881and Ser. No. 288,247 may be used to display a sequence of characterswith character generator 1224. The sequence of characters may be scannedonto element 1223 into sequential locations shown being illuminated byillumination signals 1240-1247. For example, time-shared charactergenerator 1224 may be controlled to repetitively generate a set of eightsequential characters wherein sets of these eight characters may becontinuously and repetitively refreshed or generated. As each characteris sequentially generated, a related illumination amplifier 1230-1237may be controlled to project the related character onto element 1223 inthe desired position. In a preferred embodiment, each sequentialcharacter of the set generated with generator 1224 corresponds to adifferent scanner element 1230-1237 and therefore a different projectionlocation identified with illumination signals 1240-1247; whereincharacter generator 1224 and scanner segments 1230-1237 may becorrespondingly controlled in the sequential character generation andscanning process. For example, a first character of the set may begenerated in combination with the first scanned segment 1230 beingselected to project the first character in the set onto the location ofproject screen 1223 defined by illumination signal 1240.Correspondingly, as each of the set of eight characters is sequentiallygenerated with generator 1224, one of the scanner segments 1230-1237 isselected for the corresponding character. This can be seen withreference to the scan table discussed above, wherein each sequentialscan signal B0-B7 may select a different control signal or character tobe projected along the appropriate illumination signal path of signalpaths 1240-1247 respectively. During the repetitive scan cycle, the B0control signal or character will always be projected with illuminationsignal 1240 as controlled with the scan mechanization discussed aboverelative to FIGS. 12C and 12D. Therefore, scanner 1220 of the presentinvention may be used to time share a single-character display toprovide a multiple-character display; thereby providing a low-cost andefficient multiple-character display.

Display generator 1224 may be a very small display generator such as aminiature liquid crystal display character and operator display 1223 maybe a large display such as an audience display. Proper introduction ofwell-known optics such as magnifying lenses inbetween display generator1224 and scanner 1222 or inbetween scanner 1222 and screen 1223 maypermit use of a small character generator 1224 and a large screen 1223.

Another feature of the present invention illuminates generator 1224 witha high intensity floodlight 1225, where this floodlight is shownilluminating generator 1224 in a transmissive mode but similarly may beused in a reflective mood. High intensity illumination of a smallgenerator 1224 may be used in combination with magnification optics suchas magnifying lenses placed inbetween generator 1224 and projectionscreen 1223 to provide high intensity large screen displays with aminiature character generator 1224 using low power electrical controlsignals to control or modulate high intensity illumination fromfloodlight 1225 in an illumination amplifier configuration. Further,generator 1224 may generate other symbols than characters such as a spotof light, a schematic symbol, or other such symbols. In such anembodiment, system 1220 may be used as a photo-plotter or display,wherein element 1223 may be an illumination sensitive medium such asfilm for permanent recordings, may be a frosted glass screen or afrosted coating for temporary displays, or may be other types ofillumination sensitive or projection divices.

Scanners 1200 and 1220 are discussed above as single-dimension scannersfor simplicity of illustration. It is herein intended that the teachingsdiscussed with reference to FIG. 12 be interpreted as exemplifyingmulti-dimensional scanning capability. For example, the angularrepresentations of elements 1230-1237 shown in a single-dimensionalconfiguration may be similarly shown in a multi-dimensionalconfiguration for scanning illumination signals in a plurality ofdimensions. For example, linear screen 1223 may be replaced with atwo-dimensional screen such as used in a television receiver and thesignals may be scanned in various well-known patterns such as a rasterscan used in a conventional TV receiver. Alternately, other well-knownscans may be used such as radar related scans identified as Palmerscans, A-scans, and B-scans.

Other applications and other embodiments of illumination chopperarrangements will now become obvious to those skilled in the art fromthe teachings of this invention and from prior art control arrangementsused in conjunction with mechanical chopper arrangements.

Illumination Modulators

The various arrangements described in application Ser. No. 366,714 forcontrolling illumination permits modulation of illumination forcommunication of information. The illumination amplifier arrangementshown in FIG. 1 may be used to modulate illumination signals forcommunication of information. Prior art systems modulate illumination bycontrolling the source such as with optical couplers using electricalsignals for controlling a Light Emitting Diode (LED) source and such aswith mechanical modulators used in Navy communication devices to flashdigital signals between ships. The illumination amplifier arrangement ofthe present invention permits modulation of illumination signals forcommunication of information such as modulating source illumination 102with amplifier 104 to provide modulated illumination 106; where receiver112 may include a photocell in an optical coupler arrangement or otherreceiver or the receiver may be an operator visually monitoringmodulated optical signals.

Digital modulation of illumination can be provided with logicarrangements as illustrated in FIG. 2A with gates 210 and flip-flops 200and 213. In addition, well-known digital arrangements may be used togenerate pulse code modulation, pulse width modulation, and otherdigital modulation arrangements. Signals 214 may be used to controlillumination amplifiers to digitally modulate illumination signals.Further, a pulse width modulation arrangement is discussed withreference to FIGS. 2B-2D in application Ser. No. 366,714 to providepulse width control for illumination amplifier devices. Further, asdiscussed in application Ser. No. 366,714; an analog amplitude controlcan be provided for illumination amplifiers that are responsive toanalog amplitude signals for controlling illumination in responsethereto.

Well-known optical coupler arrangements use a LED source and a photocellsensor to provide electrical isolation. In an improved arrangement,illumination amplifier 104 inbetween source 100 and photosensor 134controls illumination 102 to be modulated under control of signal 133 totransmit illumination 106 conveying the desired information tophotosensor 134.

Because of the solid-state characteristics of many source devices suchas LEDs and the batch fabricated solid-state characteristics ofillumination amplifier 104 and photosensor 134, a batch fabricatedcoupling arrangement can be provided. As an example, a monolithic arrayof source elements 100 may be provided using well-known integratedcircuit technology and may be provided in combination with illuminationamplifier devices in a batch fabricated configuration to control sourceillumination 102 with amplifier 104. The monolithic structure associatedwith solid-state source elements such as LEDs is typically asemiconductor wafer and may be passivated with well-known techniquessuch as silicon dioxide. Illumination amplifiers may be constructedusing glass substrates such as glass substrates for liquid crystaldevices, where the silicon dioxide passivation provides an illuminationamplifier substrate for combining source 100 and amplifier 104structures in monolithic form. Further, well-known monolithic processesfor producing photosensors 134 are also compatible with illuminationamplifier technology. Therefore, illumination amplifier 104 may beconfigured in a batch fabricated monolithic form in conjunction withsource 100, or photosensor 134, or both source 100 and photosensor 134.

As a further example, LEDs are packaged as individual components with abatch fabricated lens as part of the incapsulation package.Incorporation of illumination amplifiers as part of the lens structureor as part of the monolithic structure associated with source 100provides a batch fabricated illumination element that is controllablewith the very low levels of electric power.

Camera System Improvements

The camera system of the present invention is discussed in detail inapplication Ser. No. 366,714; particularly with reference to FIGS. 8-10therein. Additional improvements are discussed hereinafter.

The camera system of the present invention provides a solid-statearrangement for controlling illumination. This is contrasted to priorart arrangements such as the well-known polaroid cameras which useelectro-mechanical arrangements such as motors, mechanical shutters, andmechanical apertures for controlling illumination. The solid-stateillumination control arrangements of the present invention provideadvantages such as low cost, high reliability, low power, extensiveflexibility, and others, and further permits batch fabrication.

One embodiment of an aperture arrangement will now be discussed withreference to FIG. 8C. Aperture 820C includes concentric segments 826C,828C, and 830C. Only three segments will be illustrated for simplicityto exemplify the present invention. In a first embodiment; aperturesegments 826C, 828C, and 830C may be controlled to be eithertransmissive or reflective for three aperture conditions; where segment830C is controlled to be transmissive and segments 828C and 826C arecontrolled to be reflective for a first condition, segments 830C and828C are controlled to be transmissive and segment 826C is controlled tobe reflective for a second condition, and all segments 830C, 828C, and826C are controlled to be transmissive for a third condition. In asecond embodiment; aperture segments 830C, 828C, and 826C may all becontrolled to be reflective or may all be controlled to be transmissivein various combinations such as segments 826C, 828C, and 830C may haveone and only one segment transmissive, may have any pair of segmentstransmissive, or may have all segments transmissive for seven aperturestates. In a third embodiment; segments 826C, 828C, and 830C may becontrolled in analog fashion to be partially or totally reflectiveand/or transmissive to provide a virtually unlimited combination ofaperture conditions.

In many applications, it may be preferred to concentrate illuminationtransmission (or reflection) in a particular portion of the illuminationamplifier. For example, a lens introduces greater errors such asdistortion at the outer periphery, wherein it is desired to concentrateillumination transmission near the center of the lens. Therefore, in apreferred embodiment of a shutter control in accordance with the presentinvention, it may be desirable to control shutter 820C to minimizetransmissivity of the outer segments. For example, segment 830C may becontrolled to become transmissive in analog fashion until it iscompletely transmissive before the next segment 828C is controlled to beeven partially transmissive. When segment 830C becomes fullytransmissive, segment 828C will then be controlled to becometransmissive, and similarly when segment 828C becomes fullytransmissive, segment 826C will then be controlled to becometransmissive; thereby maximizing the reflectivity of the outermostsegments and relying on control with the innermost segments until theybecome "saturated" or otherwise limiting.

In one control embodiment, an illumination servo arrangement asdescribed in application Ser. No. 366,714 may be used to controlaperture 820C to generate an illumination control signal related to adifference between the desired and the actual illumination transmittedthrough aperture 820C. A threshold detector would be used to controleach of segments 828C and 826C; wherein an error signal below a firstthreshold would control only segment 830C, an error signal greater thanthe first threshold but less than a second threshold would be used tocontrol segment 828C with segment 830C being fully transmissive due tothe large error signal and an error signal greater than the secondthreshold would be used to control segment 826C with segments 828C and830C being fully transmissive due to the large error signal. Suchmulti-segment control is similar to the use of multi-speed resolvercontrol used in servo systems. In such systems, the one-out-of-threeresolvers for control is selected based upon the error signal magnitudeand threshold considerations. This well-known multi-speed resolvercontrol concept can be used to provide the multi-segment control for theelectro-optical resolver as discussed above.

A method for implementing electro-optical shutter and aperturearrangements will now be discussed for a lens and a liquid crystaldevice. Aperture and shutter arrangement 820C may be composed of liquidcrystal material contained between lens elements having electrodescorresponding to segments 826C, 828C, and 830C provided thereon. Commonprior art lens arrangements have combinations of concave and convexsurfaces and provide precise mating therebetween. The interlens gap orspace between lens elements may be filled with liquid crystal materialtherein and electrodes may be plated on the lens surfaces to providebatch fabricated lens, aperture, and shutter arrangements. One batchfabricated embodiment is illustrated in FIG. 4 of application Ser. No.366,714. In a preferred embodiment, inter-element gap 436 may havecurved surfaces and devices 434, 402, 403, and 435 may be shaped in theform of concave lenses, convex lenses, or various combinations ofconcave and convex lenses to provide mating therebetween and to provideinter-lens gaps such as gap 436. Gap 436 may be filled with liquidcrystal material which may have electrodes thereon to control thetransmissivity and reflectivity of the lenses for shutter control,aperture control, filter control, and combinations thereof. The shapingof elements such as elements 434, 402, 403, and 435 into lenses is wellknown in the optical art such as with lens grinding methods.

Batch fabricated devices 434 and 402 may be lens devices with matingsurfaces being concave and convex respectively and having gap 436 filledwith liquid crystal material and having electrodes formed on such lenssurfaces. In one embodiment, the concave and convex lens may beconstructed so that they do not match perfectly but provide a void atinterface 436 when placed in contact therebetween. Therefore, gap 436containing liquid crystal material may be formed as a natural gap by themating of devices 434 and 402.

Movie Camera System

In accordance with still another feature of the present invention, anelectronic control system is provided for a movie camera embodiment ofthe photographic camera system described herein and described inapplication Ser. No. 366,714 having illumination amplifier devices forcontrol of movie film exposure. This movie camera system is illustrativeof the more general features of the present invention which may beapplied to other illumination system arrangements for exposure of anillumination sensitive medium with dynamic exposure operations such asmultiple exposures synchronized with film motion as in a movie camerasystem.

Movie cameras are in wide use, where prior art movie camera controls areimplemented with mechanical aperture, shutter, and control arrangements.Mechanical devices provide for film motion and for control of a shutterusing sprocket drives and mechanical devices to provide synchronizationtherebetween. An improved arrangement will be discussed for controllingillumination of the film and providing synchronization between the filmand the shutter with electronic devices.

A movie camera control arrangement will now be described with referenceto FIG. 1. An illumination sensitive medium 130 such as movie film maybe exposed with illumination 108 controlled by illumination amplifier104. Amplifier 104 controls illumination in response to control signals133. Input illumination may be natural illumination or may be artificialillumination, where artificial illumination may be generated with source100 which may be excited with signal 132 or may be excited with rawexcitation. Command device 127 and command signal processor 128 may bearrangements discussed in application Ser. No. 366,714 and, in apreferred embodiment, may be stored program digital computer 251 whichmay have integrated circuit memory arrangements as further discussed inapplication Ser. No. 101,881. Film 130 may be transported pastillumination 108 such as with well-known sprocket drives or other knowndrive arrangements. Input illumination may be controlled by amplifier104 to expose film 130 when amplifier 104 is transmissive and not toexpose film 130 when amplifier 104 is reflective as described inapplication Ser. No. 366,714 for an illumination amplifier shutter.Control of amplifier 104 to be sequentially transmissive and reflectivehas been described in application Ser. No. 366,714 under Flasher Controlwhich may be used to flash illumination 104 to expose film 130 bycontrolling amplifier 104 with signals 133.

Synchronization of exposures and film motion may be provided with priorart mechanical or electrical arrangements. In one embodiment,synchronization may be provided electronically, where electronic signals133 are used to control illumination amplifiers 104 in synchronizismwith motion of film 130. Transducers for generating electrical signalsin response to mechanical motion are well known in the art. In oneembodiment, a switch arrangement may be controlled with a cam foropening and closing a switch in response to the rotation of a filmsprocket wheel, where the switch may provide feedback signals to commanddevices 127 or command signal processor 128 to synchronize control ofamplifiers 104 for generating flashing illumination 106 with signals133. In another embodiment, a feedback signal may be used to control thecommand device 127 or signal processor 128; which may include computer251, flip-flops 200 or 213, or other command devices. For example, theabove-mentioned sprocket synchronized switch may generate a pulse at thestart of exposure and a pulse at the completion of exposure for clockingflip-flop 213 to provide shutter signal 214A to control amplifier 104 tobe sequentially reflective and transmissive. Switch signal processingcircuits such as for switch debounce are well known in the art. In stillanother embodiment, photocell 134 may sense illumination being choppedby mechanical motion of the film drive arrangement to generate outputsignals 114 and feedback signals 120, 124, and 139 to synchronizeflasher operation. Further, synchronization of print hammer actuationwith position of a rotating print drum is similar to synchronization ofelectro-optical shutter operations with a rotating film sprocket drive;wherein such print devices are well known and are exemplified by theline printer products of Data Products Corporation of Woodland Hills,Calif.; and wherein the implementation thereof may be used for theexposure control of the present invention. Other control arrangementswill now become obvious to those skilled in the art.

A detailed description of a photographic camera is presented inapplication Ser. No. 366,714 with reference to FIGS. 9A-9C, where thearrangements provided therein for the generalized photographic cameramay also be used for a movie camera embodiment.

Computer Control Arrangement

A preferred illumination control embodiment uses computer 251 (FIGS. 2Cand 9B) for generating command signals 126 to control source 100 withsignal 132 generating controlled illumination 102 or to controlamplifier 104 with signal 133 generating controlled illumination 106 orcombinations thereof. Particular advantages are achieved by controllingamplifier 104 directly from computer 251 when computer 251 is amonolithic data processor as described in detail in the referencedcopending applications, particularly in application Ser. No. 101,881.Such a monolithic data processor is low in cost and small in size, butprovides output signals that can be used to directly excite illuminationamplifiers of large size and having complex arrays of segments; whereoutput signals from such a monolithic data processor implemented withprocesses such as MOS-FET integrated circuits have sufficient voltageand power levels to directly excite illumination amplifiers. In oneembodiment, flip-flops 200 and 213 (FIG. 2A) may be controlled bygenerating clocks 208 and 215 respectively with discrete outputinstructions from computer 251 such as described in detail in thereferenced applications. As further described in the referencedapplications, toggling of flip-flops such as flip-flops 200 and 213 maybe performed with a duty cycle related to a desired illuminationparameter, thereby providing pulse width modulated signals on lines 204and 212A to control illumination amplifiers in an analog fashion withsignals 214 and 220, as described in application Ser. No. 366,714. In analternate arrangement, pulse width modulated signals and phase relatedsignals may be provided directly from a stored program digital computersuch as computer 251 as described in application Ser. No. 366,714 underAnalog Excitation and in the other referenced applications.

Segment Arrays

Illumination control has been described herein relative to illuminationamplifier areas having desired shapes. In one embodiment of illuminationcontrol devices in accordance with the present invention, illuminationamplifier devices are arranged having an array of miniature segments1300 (FIG. 13) which will herein be described as micro-segments over anarea, where illumination control characteristics of that area may bedefined as a sum or an integral of the effects of a multitude ofmicro-segments controlled individually or as groups of micro-segments.In one embodiment, the micro-segments may be similar to the dot patternsassociated with the printing art and known as screened or half-tonearrays of dots. It is well known to those skilled in the printing artthat an array of dots in a screened configuration provides an imagehaving the combined effect of a plurality of the dots in a particulararea to provide shades of grey or shades of color for the printingprocess. In a manner analogous to the use of screened printing concepts,an array of micro-segments can be controlled to transmit and reflectillumination; wherein the characteristics of the controlled illumination108 is related to the combined effects of multitudes of micro-segmentsin a particular area 1300.

In one embodiment, control of illumination intensity or color or bothmay be provided with a plurality of sets of micro-segments wherein theillumination amplifier device contains micro-segments from each setinterspersed together. For simplicity of discussion, two sets ofinterspersed micro-segments will be considered. It may further beassumed that a first set of micro-segments 1310 shown shaded coversone-third of the illumination amplifier area 1300 and a second set ofmicro-segments 1312 shown non-shaded covers the other two-thirds of theillumination amplifier area. When both sets 1310 and 1312 are controlledto be transmissive, all of illumination 102 will be transmitted asillumination 108 and no illumination will be reflected as illumination110. Similarly, when the first set is excited to be transmissive and thesecond set is excited to be reflective, one-third of illumination 102will be transmitted as illumination 108 and two-thirds of illumination102 will be reflected as illumination 110. When both sets are excited tobe reflective, substantially all illumination 102 will be reflected asillumination 110. Therefore, two sets of interspersed micro-segments maybe used to provide four states of illumination from full transmissivityto full reflectivity. Further, a larger number of sets of micro-segmentscan be provided to control the transmitted and reflected illumination,where digital control of sets of micro-segments can provide variationsin transmitted and reflected illumination intensity. Therefore, a formof analog control of illumination intensity can be provided by digitalcontrol of a plurality of sets of micro-segments. Still further, themicro-segments may have different shapes and different dimensions andsets of micro-segments may be related to different densities such aswith different size micro-segments and different quantities ofmicro-segments, where the embodiment described above can be implementedhaving the second set of micro-segments providing twice the densityeither with twice as many of the same size micro-segments or with thesame quantities of micro-segments being twice as large as those of thefirst set or other combinations of size and quantity. Further,micro-segment size and quantity may be determined and may be intermixedin combinations and arrangements to meet the special requirements of theparticular application.

From the above discussion, it can be seen that the net effect of anillumination amplifier arrangement may be controlled to providevariations in intensity, in color, or in other characteristics usingonly digital control of micro-segments. Further, micro-segments can alsobe controlled with analog excitation to provide additional flexibilityfor illumination control. Still further, micro-segments can be providedhaving different color characteristics such as described for colorcontrol in application Ser. No. 366,714 to provide color patterns suchas is well known in the printing field with color screened type printingtechniques.

Yet further, arrays of micro-segments or individual micro-segments canbe selected with coincident select excitation to provide the desiredillumination control. Such an arrangement may be used for a display suchas discussed herein and in application Ser. No. 366,714 for the OperatorPanel and the Audience Display System or may be used for arrangementssuch as for a television receiver. Color television receivers are wellknown in the art having dot patterns of colored phosphor arranged on ascreen and selected with an electron beam scanning the phosphor pattern.A solid state television display may be provided with micro-segments ofillumination amplifier devices either individually selectable with alinear select arrangement or, for greater economy, selectable with amultiple dimensional select arrangement such as a two dimensional orcoincidence selection arrangement. In such a television display system,arrays of micro-segments may comprise a set of three micro-segments eachhaving a different color such as with phosphorous segments on a colortelevision tube and using the color control concepts described inapplication Ser. No. 366,714 under Color Control and applied to themicro-segment configuration. Therefore, individual control of each ofthree colored micro-segments associated with each set of micro-segmentsmay provide the intensity of the three primary colors, thereby yieldingthe equivalent of a spot having a color related to the combination ofthe intensities of the three colors of that set of micro-segments asdescribed in application Ser. No. 366,714 under Audience Display System.Still further, sequential selection of each set of three micro-segmentswill provide the equivalent of the roster scan associated withwell-known color television sets.

The above-mentioned display system having sets of micro-segments may beused for black and white television sets, color television sets, andgeneral display systems such as described in application Ser. No.366,714 under Audience Display System.

Multiple Electrode Logic

The present invention has been described for simplicity using a pair ofelectrodes providing an electric field therebetween. One feature of thisinvention provides a plurality of electrodes which may be a quantitygreater than two electrodes each having a different control signal forexcitation for providing greater control flexibility. For simplicity,this arrangement having a plurality of control signals will be describedas summation of electrostatic fields such as with a liquid crystaldevice. It is herein intended that such an arrangement exemplify moregeneralized inventive features wherein a plurality of electrodes eachhave a different control signal and that at least one return electrodebe provided as may be required for control of the illumination amplifierfrom said plurality of electrical control signals.

One embodiment of the multiple control feature of the present inventionwill be described with respect to FIG. 8B, where a plurality ofelectrodes 826, 827, and 830 are provided on one side of theelectro-optical material in conjunction with a common electrode on theopposite side of the illumination amplifier material, wherein theelectrostatic field between control electrodes 826, 828, and 830 and thecommon electrode may be defined with well-known electrostatic theorysuch as described in the textbook Electromagnetic Fields and Waves byRamo and Whinnery. Any number of control electrodes may be providedwherein the combination of excitation fields, the magnitudes ofexcitation fields, and other such characteristics define the totalexcitation field for controlling the illumination amplifier materialsuch as the liquid crystal material. The net effect of a plurality ofsignals and fields is related to the summation of the excitationsignals, the geometry of the electrodes, the geometry of theillumination amplifier structure, and other such considerations that canbe analyzed and designed with such well-known electrical field theory.

The plurality of electrodes illustrated in FIG. 8B is merely exemplaryof the general features of the present invention, where the electrodesmay be shaped, positioned, and oriented therebetween to provide thedesired field pattern and where said plurality of electrodes may besquare electrodes within square electrodes as illustrated in FIG. 8B,concentric circular electrodes as illustrated in FIG. 8C, geometricpatterns of electrodes as illustrated in FIG. 8A, electrode patterns asillustrated in FIG. 11, micro-segment electrodes interspersedtherebetween as described with reference to FIG. 13 and other patternsof electrodes to provide the desired fields for excitation.

In one embodiment, a pair of electrodes may be interspersed so that thefield pattern of either electrode can excite the liquid crystal materialto be reflective and the absence of excitation from both electrodes willrender the liquid crystal material to be transmissive. This arrangementis equivalent to a logical OR gate, where excitation by either one or byboth electrodes will control the amplifier to be reflective and whereexcitation on neither electrode will control the amplifier to betransmissive. In a complement form, a logical AND gate may be providedwith complement-excitation (non-excitation) on both electrodes toprovide transmissivity, but the absence of complement-excitation(non-excitation) on either electrode will provide reflectivity.

In yet another embodiment, the two control electrodes may have inverseexcitation such as positive and negative DC fields or in-phase andout-of-phase AC excitation; where excitation on a first controlelectrode may provide reflectivity, excitation on neither electrode mayprovide transmissivity, and excitation on both electrodes may provide acancellation effect equivalent to the non-excitation state therebyproviding transmissivity; thereby providing an A.B logical operation.

The above-described arrangement may use analog excitation. In one suchembodiment, excitation from a plurality of electrodes may be summedeither in combinations of inverted and non-inverted forms to provideaddition and subtraction with addition and subtraction of fieldsrespectively based upon the related excitation magnitudes. Various typesof analog excitations such as analog amplitude excitation, pulsemodulated excitation, combinations of analog amplitude and pulsemodulated excitation, and other such forms of excitation may be providedfor the plurality of control electrodes feature of the presentinvention.

Control, arithmetic, logical, and other operations may be provided suchas with the geometry of the electrodes, the inter-relation of theelectrodes, and other such design parameters. For example, a firstelectrode may be provided for primary excitation and a second electrodemay be provided having a geometric relationship with said firstelectrode to provide fringe fields that are a function of the geometryof the electrode relationships, wherein the effect of the secondelectrode may provide a non-linear control, mathematical, or digitalrelationship. Such non-linear relationships may be logarithmic,exponential, geometric, and other desired functions of excitational.

A still further feature of the present invention may provide a greaternumber of electrodes such as 3 electrodes, 4 electrodes, or 5 electrodesto provide combinations of the operations described above. In oneexample, digital excitation for a first electrode may provide an enableand disable control operation, bias excitation for a second electrodemay provide bias control related to a predetermined level, a thirdelectrode may be excited with a mathematical control function, a fourthelectrode may be excited with a non-linear function, and additionalelectrodes may be used to perform other such functions.

Fringe Control

The electric fields and waves art such as described in the textbookElectromagnetic Fields and Waves by Ramo and Whinnery show that thefields outside of the electrode area may provide a fringe field affect.Particular advantage may be achieved with fringe fields when used withliquid crystal devices, exemplary of a general inventive feature havingelectrodes offset therebetween to provide fringe fields therebetween forexcitation of liquid crystal material to exemplify this inventivefeature.

A simplified description of the fringe control inventive feature willnow be provided with reference in FIG. 11. For simplicity of discussion,it will be assumed that each segment 1142-1145 and 1152-1155 has acorresponding electrode thereunder; colocated, similarly shaped anddesignated with an A symbol. For example, segment 1144 is assumed to belocated directly above and on the other side of the controlled liquidcrystal material of a corresponding similarly shaped electrode 1144A.Excitation of electrode 1144 and return electrode 1144A directlythereunder provides a controllable segment shaped as segment 1144.Excitation of segment 1145 and return segment 1145A directly thereunderprovides a controllable segment shaped as segment 1145 and furtherprovides a fringe pattern being most intense at the transition betweensegments 1144 and 1145 and may vary in intensity such as from the centerof arrangement 1140 outward to the right therefrom. Similarly, intensitymay decrease in relation to the distance from the intersection ofsegments 1144 and 1145 and may vary as a function of the distance fromthe center of arrangement 1140. One analysis of the intensity may bemade from well-known field theory, where the intensity of the field maycontrol intensity of the reflectivity or transmissivity of theillumination amplifier device.

From the above description, it can be seen that complex patterns ofintensities can be provided by excitation and return electrode shapesand positions therebetween. Further excitation of a plurality ofelectrodes such as electrodes 1142-1145 and 1152-1155 and havingcorresponding return electrodes 1142A-1145A and 1152A-1155A thereundercan selectively provide complex field arrangements therebetween forproviding different geometric patterns and intensities of illuminationamplifier action.

The term fringe arrangement is herein intended to mean control ofillumination amplifier devices having offset, or non-orthognal, orskewed, or other such relationships and in particular offset electrodesfor providing non-perpendicular electrostatic fields therebetween forcontrolling illumination amplifier devices.

Still further, such offset arrangements may be partially offset, wheresegments 1144A and 1145A together may define a return electrode andsegments 1144 and 1145 together may define an excitation electrode;where segment 1144 thereby defines the common area or superimposed areaof return electrode 1144A and 1145A and excitation electrodes 1144 and1145 and segments 1145 and 1154 thereby define offset portions of theelectrodes such as for fringe effects. In one embodiment, common segment1144 may be larger than segments 1145 and 1154 and therefore segment1144 may provide the primary illumination control with fringe segments1145 and 1154 providing only secondary illumination control such as edgeor fringe effects, possibly for a soft glow area around the edge ofdisplay segments. In still other embodiments, fringe segments 1145 and1154 may be larger than segment 1144 and therefore segments 1145 and1154 may provide the primary illumination control.

Additional Considerations

The arrangements and methods described herein and in application Ser.No. 366,714 are useful individually and in combinations and further maybe used in many new and unique applications either individually or incombinations to provide improvements in prior art equipment and methods.Some of these new and unique applications are described hereinafterexemplary of the broad range of applicability of the features of thepresent invention. It is intended that these specific applicationsdiscussed hereinafter be exemplary of the very broad applicability ofthe features of the present invention.

The system of this invention is discussed relative to photo-electricdevices such as the well-known liquid crystal devices. Many of theapplications described herein may be described in terms of the"illumination amplifier" concept and embodiment. It is herein intendedthat the scope of this invention be broadly interpreted and beapplicable to a wide range of electro-optical, electro-chemical, andother such devices for controlling illumination that may be used toprovide the capabilities described herein which are exemplified withliquid crystal devices.

Pertinence Of Material Incorporated-By-Reference

The instant application (as with the parent application Ser. No.366,714) incorporates-by-reference copending applications and patentsthat contribute to the disclosure of the present invention. Thepertinence thereof will now be discussed.

The pertinence of copending application Ser. No. 101,881 will now bediscussed.

FIG. 1 of application Ser. No. 101,881 sets forth a data processor 12for controlling machine 24 with servos 20-22 and discrete controlsignals 26 and with operator panels 14 and 18. Control of machine 24with servos and discrete controls is similar to control of theillumination amplifiers of the present invention with servos anddiscrete control devices. For example, the machine control servos aredisclosed using pulse-modulated methods similar to the methods discussedin the instant application. Further, discrete signals can also be usedfor controlling illumination amplifiers and for providing computerfeedback from illumination amplifiers. Still further, the discrete andalpha-numeric displays of display panel 18 can use the illuminationamplifier arrangements of the instant application and control panel 14can use the illuminated switches of the present invention, therbyfurther describing the usage environment of the illumination amplifierdisplays.

FIG. 2 of application Ser. No. 101,881 sets forth the detailed operatorcontrol and display panel environment for usage and operation of theillumination amplifier devices of the present application. Inparticular, FIGS. 2C and 2D provide the interface between a monolithiccomputer and an operator panel which can incorporate the illuminationamplifier features of the present invention. Further, this computerinterface is exemplary of more general uses discussed in the instantapplication for control of illumination amplifiers with a digitalcomputer.

FIGS. 3 and 16-19 of application Ser. No. 101,881 exemplifies a servocontrol with a computer interface, wherein the computer-commanded servocontrol is usable with the illumination amplifier devices of the presentinvention in substitution for machine tool 24 of the embodimentdiscussed in application Ser. No. 101,881.

FIGS. 5-12 of application Ser. No. 101,881 sets forth architecture ofone embodiment of a monolithic computer exemplary of the moregeneralized computer usable with the illumination amplifier features ofthe instant invention.

FIG. 13 of application Ser. No. 101,881 exemplifies input and outputcontrol between a computer and external devices which may be theillumination amplifier devices of the present invention. For example,discrete inputs DI-0 to DI-11 may be used to monitor discrete statessuch as sensor signals that monitor controlled illumination. Discreteoutputs D0-1 to D0-11 may be used to control illumination amplifierdevices such as by exciting the illumination amplifier either with astatic DC output level set into a flip-flop such as by togglingflip-flops I1 to I4 with discrete outputs D0-8, D0-4, D0-5, and D0-6respectively; or by directly pulsing the illumination amplifier devicesuch as with a pulse rate modulated signal; or otherwise controllingillumination amplifiers through well-known interface electronics underdiscrete output control. Whole word outputs OW-0 to OW-11 may be used togenerate whole number commands such as with packed discretes to thelamps discussed with reference to OW-11 outputs, or to numeric displaysdiscussed with reference to OW-9 outputs, or with analog magnitudeinformation to a digital-to-analog converter which is exemplified withthe disclosure set forth in copending application Ser No. 325,933discussed hereinafter. Latched discretes and control signals are showngenerated with the OW-8 signal loading C-register 260 and generating theC6Q to C15Q signals. Input word signals IW-0 to IW-7 are shown loadingfeedback information into the computer such as packed discretes fromsensors; whole number digital signals from an analog-to-digitalconverter such as disclosed in application Ser. No. 325,933 discussedhereinafter; or other computer input signals.

FIGS. 14A and 14B of application Ser. No. 101,881 further exemplifycomputer inputs such as loading packed signals T0-T8, P0-P3, M0-M2,J0-J2, and S0-S11 into the computer and also exemplify the output ofpacked control signals from Z-register 268 with storage flip-flopsZ0-Z11.

FIG. 15 of application Ser. No. 101,881 discloses packed output controlsignals TS-0 to TS-7 and encoded input signals S0-S3 and others.

FIGS. 16-19 of application Ser. No. 101,881 disclose a servo arrangementthat is exemplary of servos that may be used for illumination control inplace of the machine control.

The pertinence of applications Ser. No. 134,958 and Ser. No. 135,040will now be discussed. These applications are directed to servo controlof a machine with a computer, wherein the machine servo control is alsoexemplary of an illumination amplifier servo control. This control isdisclosed using hardwired servo loops commanded by a computer in anopen-loop fashion and also in an alternate embodiment with the computerbeing in the servo loop. Further, pulse modulated control under computerprogram control is disclosed wherein the computer may be in the servoloop directly exciting the control device which may be an illuminationamplifier and by directly monitoring the feedback device which may be anillumination sensor.

The pertinence of copending application Ser. No. 288,247 will now bediscussed. In particular, application Ser. No. 288,247 is directed tointeraction between the operator panel and the computer of theabove-discussed application Ser. No. 101,881; wherein the computer flowdiagrams of FIGS. 3 and 5-7 of application Ser. No. 288,247 disclose theprocessing and communication implemented with the hardware diagrams ofFIGS. 1, 2, 8, and 9 corresponding to related figures of applicationSer. No. 101,881 as discussed above.

The pertinence of copending application Ser. No. 291,394 will now bediscussed. This application is directed to control of a machine by acomputer using discrete signals which; is exemplary of control of theillumination amplifier arrangements of the present invention with acomputer using discrete signals. FIGS. 1, 2, and 4-6 of application Ser.No. 291,394 are similar to related figures of application Ser. No.101,881 but application Ser. No. 291,394 provides more detaileddisclosure relative to discrete control. In application Ser. No.291,394; FIG. 7 provides a more detailed disclosure of a discrete inputand output interface for the computer and FIG. 8 provides programcontrol disclosures relative to controlling of external devices;exemplary of control of illumination amplifier devices with discretesignals.

The pertinence of application Ser. No. 302,771 will now be discussed.This application is also directed to control of a machine with variouscontrol methods including servos and adaptive control; exemplary ofcontrol of illumination devices in accordance with the presentinvention. FIGS. 1, 2, and 4A of application Ser. No. 302,771 aresimilar to related figures in application Ser. No. 101,881 as discussedabove. FIGS. 3 and 4B of application Ser. No. 302,771 are exemplary ofcontrol arrangements applicable to the illumination control devices ofthe instant application. FIGS. 6 and 8 of application Ser. No. 302,771are exemplary of signal processing for control of devices and aredirectly usable with illumination devices. FIGS. 7 and 10 of applicationSer. No. 302,771 are exemplary of computer operations for control ofdevices such as the illumination devices of the present invention.

The pertinence of copending application Ser. No. 325,933 will now bediscussed. Although this application is directed to audio response, manyof the audio control functions are exemplary of illumination controlfunctions. FIGS. 1 and 2 of application Ser. No. 325,933 are similar torelated figs of copending application Ser. No. 101,881 discussed aboveand are discussed in greater detail in application Ser. No. 325,933.FIG. 3 of application Ser. No. 325,933 sets forth a detailedanalog-to-digital converter, digital-to-analog converter, and computerinput/output structure usable in combination with the computeroperations of FIG. 6 and are exemplary of generalized converterinput/output operations usable with the illumination devices of thepresent invention. FIG. 5 of application Ser. No. 325,933 is exemplaryof generalized computer operations of controlling external devices whichmay be the illumination devices of the present invention.

The pertinence of copending application Ser. No. 550,231 will now bediscussed. This application is directed to filtering, signal processing,communications, and memory systems which may be implemented withillumination devices disclosed in the instant application. For example,analog and digital illumination computing devices disclosed withreference to FIG. 3 of the instant application may be used to implementthe devices of application Ser. No. 550,231 such as disclosed in FIGS.4, 6 and 7 therein. Further, the illumination devices of the instantapplication may be usable in combination with or in replacement of theCCD devices of application Ser. No. 550,231 as set forth in FIG. 9therein.

In view of the above, the disclosures of the referenced copendingapplications herein incorporated-by-reference exemplify arrangements andmethods that are usable with the illumination devices of the presentinvention and are intended to be usable in combination therewith. Forexample, the servo control arrangements disclosed in said copendingapplications are intended to be used in replacement for the servocontrol arrangements disclosed in the instant application and are ingeneral intended to be usable in combination with the illuminationcontrol devices of the instant application. Further, the computercontrol and interaction disclosed in said copending applications isintended to be usable in combination with the illumination controldevices of the present invention where for example the computer 251disclosed in FIGS. 2 and 9 of the instant application is intended to besupplemented with the computer disclosure of said copendingapplications.

Projection Display Arrangement

An illumination amplifier projection display arrangement in accordancewith the present invention has been described in parent U.S. Pat. No.3,986,022 and in copending application Ser. No. 727,330 wherein thefollowing discussion will more specifically describe preferredembodiments thereof.

Conventional display arrangements typically require an image generatorto generate the illumination as a source, wherein the illuminationgenerated by the image generator such as a conventional television (TV)receiver therefore has relatively low intensity. It is well known thatprojection and magnification of an image reduces intensity of the image.Therefore, it was not practical to project prior art images generatedwith such image generators. In accordance with the present invention, animage generator is provided that is an illumination amplifier whichcontrols externally generated illumination such as through reflectivityand transmissivity characteristics of the illumination amplifier.Therefore, intensity of the image is a function of intensity of theincident illumination controlled with the illumination amplifier imagegenerator, where very high image intensities may be provided byilluminating the amplifier image generator with high intensityillumination. In accordance with the illumination amplifier feature ofthe present invention, an image generator may be used in a magnifyingprojection display system providing high intensity magnified projectiondisplays by illuminating an amplifier image generator with highintensity illumination.

The projection display feature of the present invention will now bediscussed in the embodiment of a projection audience display system andparticularly in the embodiment of a large screen television display.This preferred embodiment is intended to exemplify but not to limit thegeneral features of the projection display system of the presentinvention.

A basis for the invention features discussed hereinafter are set forthin parent U.S. Pat. No. 3,986,022; other related applications discussedtherein; and copending application Ser. No. 727,330 For example, thegeneral features of excitation; batch fabrication; closed loop control;computer control; camera systems; choppers, scanners, and modulators;traffic light controls; and other such implementations discussed in saidrelated patents and applications are directly applicable to theprojection display system and are intended to be used in combinationstherewith. For example, said U.S. Pat. No. 3,986,022 and applicationSer. No. 727,330 discloses a large screen audience display system atpages 104-109, a television display at page 109 lines 28-32, a CRTembodiment at page 84 lines 8-11, a camera embodiment at pages 84-96,color control at pages 61-63 and pages 106-109, multiple source controlat pages 99-103, high intensity projection at page 104 lines 28-35,closed loop control at pages 46-49, storage of displayed signals such aswith a capacitor at pages 58-60, and batch fabricated arrangements suchas at pages 41-45.

Further, copending application Ser. No. 727,330 includes the abovedisclosures in addition to the disclosures of television embodiments andscanning embodiments at page 128 lines 21-35, projection of magnifiedhigh intensity images at page 128 lines 1-12, a slide projectorembodiment at pages 146 and 147,fiber optic embodiments at pages 163 and164, batch fabricated arrangements at page 159 line 30--page 160 line 16and computer control at pages 139 and 172-177 therein.

It is herein intended that the above-listed disclosures from allcopending applications and the other disclosures from said copendingapplications be considered as usable with the projection display systemand are intended for use in combinations therewith, wherein the use ofthese disclosed implementations and methods may be applied to theprojection display system of the present invention in a manner that willbecome obvious to those skilled in the art from the teachings herein.For example, the projection display system may be batch fabricated, mayuse fiber optics, may be projected such as with slides or movies, may beprojected with high intensity and magnification characteristics, mayutilize computerized closed loop control, may use a light pen, may usecircuitry discussed for illuminated switch signal storage, may use colorcontrol, may be used to expose an illumination sensitive medium, may usemultiple sources and multiple colors, and may be used in conjunctionwith other teachings provided in the instant application and in thereferenced copending applications.

A preferred embodiment of the projector arrangement will now bediscussed with reference to FIG 14. Projector 1410 includingillumination amplifier 104 generates projected illumination 1414 to aprojection screen 1451. Projector 1410 includes image generator 1450 andpost-optics 1436. Image generator 1450 generates controlled illumination1435 and 1437 to post-optics 1436 for post-processing of illumination togenerate projection illumination 1414. Post-optics 1436 may be composedof conventional optics arrangements and may include magnifying opticssuch as provided in conventional projectors including slide projectorsand movie projectors. Image generator 1450 may include illuminationsource 100 which may be any of many well-known sources including lightbulbs such as projector bulbs and may be other types of illuminationsources such as flame sources used on the well-known searchlights.Source 100 may be controlled with control signal 132 generated withcontrol electronics 127, 128 as discussed in Pat. No. 3,986,022 withreference to FIG. 1 therein. Illumination from source 100 may be highintensity illumination for projection display and may be concentratedwith reflector 1441 which may be well-known reflector arrangement suchas used on flashlights, slide projectors, or searchlights. Sourceillumination 102 may include direct illumination from source 100 andreflected illumination from reflector 1441. Source illumination 102 maybe pre-processed with pre-optics 1433 which may include well-knownoptical devices such as accumulating and focusing lenses. Pre-processedillumination 1434 from pre-optics 1433 may be controlled withillumination amplifier 104 for generating illumination images.Illumination amplifier 104 may operate in a transmissive mode generatingtransmissive image 1435 or may operate in a reflective mode generatingreflective illumination 1437. Illumination amplifier 104 may operate inresponse to control signals 133 from control devices 127, 128 asdiscussed in U.S. Pat. No. 3,986,022 with reference to FIG. 1 therein.

Illumination images 1435 and 1437 may be processed with post-optics 1436for focusing, magnification, and other well-known optical functions. Ina simplified embodiment, projector 1410 may be a well-known slideprojector having an illumination source 100, reflector 1441, pre-optics1433, and post-optics 1436; wherein illumination amplifier 104 may besubstituted for the well-known slides in the slide projector.

Illumination amplifier 104 may be a monochromatic arrangement forgenerating a single-color image 1435 and 1437 or may be multi-coloredarrangement for generating colored images 1435 and 1437; where colorarrangements are discussed with reference to FIGS. 6D and 11 of U.S.Pat. No. 3,986,022. In one embodiment, color may be introduced using acolored source 100, colored filters in pre-optics 1433, colored filtersin post-optics 1436, or colored segments of illumination amplifier 104.Other methods of introducing color will now become obvious from theteachings herein.

Projection screen 1451 may be any well-known screen. For example,conventional movie and slide projector screens may be used for screen1451. Alternately, screen 1451 may be a wall of a building which mayhave a desired coating such as a light colored paint, beaded material,or other such coatings. Alternately, screen 1451 may be a frosted glassscreen or other screen material which might be illuminated from one sideand viewed from the other side. Screen 1451 may be part of projector1410 such as with the self-contained screens in TV sets or may be aremote screen such as a slide projection or movie projection screenlocated remotely from projector 1410. Further, screen 1451 may be ascoreboard, billboard, or other large-scale outdoor-type screen. Yetfurther, screen 1451 may comprise a plurality of different screens andpost-optics 1436 may include prism or beam splitter type optics toproject each of a plurality of identical images 1414 on different onesof a plurality of screens 1451 for viewing from different locations suchas different sides of a scoreboard.

An alternate embodiment for a color projector will now be discussed withreference to FIG. 14B. Multiple-color projector 1411 comprises threechannels of projectors similar to projector 1410 discussed withreference to FIG. 14A. Each of the three image generators 1450 maygenerate either transmitted or reflected illumination images topost-optics 1436 to generate projected image 1414. Each channel,comprising image generator 1450 and post-optics 1436, may represent adifferent color such as red, green, and blue colors indicated by the R,G, and B symbols associated with the three related channels ofillumination. Triple image generators 1452 may generate transmittedillumination 1435, reflected illumination 1437, or combinations thereof.Triple post-optics 1454 may project the three colored illumination beamsto screen 1451 so that all three colored beams 1415 are superimposed andhave registration therebetween to provide a focused image on screen 1451that represents the combination of all three colored images 1415.

Another alternate embodiment will now be discussed with reference toFIG. 14C. Triple-image generator 1452 may generate three illuminationimages which may be transmitted illumination 1435 or reflectedillumination 1437 or combinations thereof for processing with combinedpost-optics 1455. Combined post-optics may combine the threeillumination beams such as with accumulating and focusing lenses togenerate a single combined colored image beam 1416 for projection ontoscreen 1451.

Still other alternative embodiments will now be discussed with referenceto FIGS. 14D and 14E which represent reflection projection arrangementsin contrast to the transmission projection arrangements discussed withreference to FIGS. 14A-14C. In these embodiments, projectors 1410-1412generate projection illumination 1414-1416 which is reflected from imagereflector 1442 to focus on screen 1451. Reflector 1442 may be amagnifying reflector for accumulatimg. magnifying, focusing, andprojecting the image onto screen 1451 as reflected image 1417. A singlebeam projector 1410 and 1412 (FIG. 14D) generates projected images 1414and 1416 respectively as discussed with reference to FIGS. 14A and 14C.A triple beam projector 1411 (FIG. 14E) generates triple image beams1415 in a reflection embodiment as discussed with reference to FIG. 14Dabove using reflector 1432 to reflect images 1417 to screen 1451.

Projector 1410 may include a zoom capability. The zoom capability whichmay be implemented electronically or optically. For the electronicimplementation, command arrangement 127 and 128 generating controlsignals 133 may computationally enlarge the image by controllingamplifier 104 to generate a larger optical image under electroniccontrol. Alternately, post-optics 1436 may include a zoom lenscapability such as used on slide and movie projectors and otherwell-known systems to enlarge or reduce image 1414 projected on screen1451. Zoom capability may be either manual or automatic as implementedin well-known projection systems.

A large-screen-projection television embodiment will now be discussedwith reference to FIG. 14. Advances in prior art TV systems and knownprojection TV systems are discussed in the article New Season's Color TVSets Slate Major Role For Large-Scale Integration by Gerald M. Walker inthe Sept. 30, 1976 issue of Electronics magazine which isincorporated-by-reference herein. This article points out the importanceof projection TV systems and the configuration of prior art systems.Such prior art systems use projection tubes, projection lanterns, CRTs,and a trinitron tube; where a major limitation of these prior artarrangements is the low intensity levels available with theseprojectors. The illumination amplifier feature of the present inventionsolves the intensity problem and permits a fully solid-state arrangementusing low voltage electronics which eliminates vacuum tubes andexpensive high-voltage electronics.

In prior art systems, the image generator such as the cathode ray tube(CRT) must generate the image having the desired intensity. Theintensity available with CRTs and other such devices is very low and notpractically suitable for projection particularly for projection of largeimages with significant magnification. The image generator of thepresent invention does not generate its own illumination but controlsexternally generated raw illumination as an illumination amplifier. Forexample, illumination amplifier 104 is not a source of illumination butmerely modulates or amplifies illumination from source 100, wherein lowlevel electrical signals 133 may be used to control high intensityimages 1435 for projection with post-optics 1436. It is estimated thatintensity of image 1435 using illumination amplifier 104 may be hundredsor thousands of times more intense than the intensity of imagesgenerated with conventional techniques such as CRTs. For example,conventional televisions using CRTs are marginally acceptable, where theCRT is adequate for a darkened room and a non-projection system. If a24-inch CRT TV picture were projected to a four-by-six-foot largescreen, the intensity of the projected image would be approximatelyone-sixth of the intensity from the CRT in a non-projectionconfiguration. Obviously, this one-sixth of normal TV intensity would beinadequate. Therefore, exotic techniques, higher voltage circuitry, andother expensive methods are used to increase image intensity usingconventional techniques.

In the system of the present invention, a small illumination amplifierdevice 104 may be used in conjunction with a high intensity source 100to generate high intensity large-screen projection images 1414. Presentphoto-lithographic integrated circuit techniques make it relativelysimple to provide small 0.001-inch elements on a substrate. Therefore,the 512-by-512-point resolution of a TV CRT may be implemented on anillumination amplifier device such as a liquid crystal device ofapproximately one inch square. Illumination of a small image such as aone-inch-square image formed on illumination amplifier 104 using highintensity raw illumination 1434 will permit projection and magnificationof the small image to large dimensions with post-optics 1436 forprojection onto screen 1451.

In a TV embodiment, conventional TV signals may be received andprocessed with conventional TV electronics. Video signals may beelectronically scanned across illumination amplifier 104 with well-knownelectronic scanning methods such as the TV raster scan. Each amplifierelement may have a memory element related thereto such as a flip-flop orcapacitor as discussed with reference to FIG. 6C in U.S. Pat. No.3,986,022. Accessing of an array of elements such as liquid crystalelements is well known in the art such as two-dimensional coincidentexcitation arrangements used with core memory systems.

The projector arrangement discussed above will now be discussed withreference to FIG. 14F to illustrate use in a complete TV receiversystem. TV signal 1459 may be received with TV receiver 1460 comprisingwell-known antennas and tuner, RF, video, IF, and audio circuitry togenerate video signals 1461 to TV signal processor 1462. Signalprocessor 1462 may include well-known TV signal processing circuitrysuch as used with well-known solid-state image generators. Control 127and 128 generates control signal 133 in response to processed signal1463; wherein signal 133 may include scan control and intensity controlsignals and may further include pulse width modulated or other signalcharacteristics such as discussed in said U.S. Pat. No. 3,986,022.Control signal 133 controls illumination amplifier 104 to controlillumination 1434 to generate controlled illumination 1435, 1437 whichis projected with post-optics 1436 as projected signal 1414 toilluminate screen 1451; as discussed with reference to FIG. 14 herein.

In view of the above, it can be seen that the arrangement disclosed inFIGS. 14A-14E can be implemented in combination with well-known TVfront-end circuitry to provide an implementation of a complete TVreceiver.

The arrangement discussed with reference to FIG. 14 may be implementedin the form of a conventional projector arrangement such as a TVreceiver or in the form of a holographic projector. In the conventionalprojector arrangement, source 100 may be non-coherent illuminationsource such as a zenon lamp, mercury vapor lamp, incandescent lamp, orother well-known lamps which may be of a high intensity variety andillumination amplifier 104 may provide conventional images such asviewed on a conventional TV display. Alternately, this projection systemmay be implemented with a coherent illumination source 100 such as alaser or other coherent source and illumination amplifier 104 maydisplay holographic patterns such as interference patterns forgenerating and projecting holographic images as images 1435, 1437, and1414. In a conventional projection arrangement, a projected illuminationimage may be projected upon a screen to provide a two-dimensional image.In the holographic embodiment, illumination images 1435, 1437, and 1414may be holographic images and may be projected on a screen such asscreen 1451 or may be projected without a screen for providingthree-dimensional holographic images.

In accordance with the holographic projector arrangement discussedabove, a holographic TV camera can be provided, wherein holographicimages may be provided with the appropriate optics such as lenses and aconventional television camera may be used to take moving video picturesof the holographic interference patterns for transmission to thereceiver, discussed with reference to FIG. 14F, to provide athree-dimensional holographic TV system.

Because of the integrating effect of the human eye, photographic film,etc. and because each illumination image portion is independently formedin a non-coherent system, a scanned image such as with the raster scanin a conventional TV system is acceptable. In a holographic system,dependence is placed on interference between phases of different imageportions. Therefore, it may be desirable to provide projection of acomplete holographic image rather than projection of a scanned image.

In one embodiment, a holographic image may be scanned onto illuminationamplifier 104 with control signal 133; may be temporarily stored onamplifier 104 such as with capacitors; and coherent source 100 may bede-energized during scanning. After the holographic image has been fullystored on amplifier 104, source 100 may be energized to project storedimage 1435, 1437 as illumination 1414. In a multiple-channel system suchas discussed with reference to FIG. 14B, the miltiple channels may bescanned in an interleaved manner and may be sequentially projected. Forexample, while a red image is being scanned in the red channel R andtherefore non-projecting, the green channel G and blue channel B may beprojecting green G and blue B images 1415. Such interleaved operationmay be implemented in the form of a well-known refresh arrangement andimage information to be scanned may be stored in memory 1464 performinga buffer or refresh function.

Because of said integration effect, the pulsed operation of theholographic system is analogous to the scanned operation of aconventional TV system. Pulsing of lasers and control thereof is wellknown in the art.

The projection feature of the present invention may be used in arecording embodiment, where screen 1451 may be an illumination sensitivemedium 130 such as film, light sensitive paper, a phosphor surface, orother well-known illumination sensitive mediums, where exposure ofmedium 130 is discussed in U.S. Pat. No. 3,986,022. Projection of animage onto medium 130 used in place of screen 1451 can provide apermanent record of information displayed with amplifier 104. In thisrecorder embodiment, amplifier 104 may be a physically small elementsuch as one-square-inch television image or may be a physically largeelement such as a ten-square-inch arrangement for greater resolution.Post-optics 1436 may magnify or reduce image 1435, 1437. Magnificationof a small image may be provided for using a smaller, lower resolutionamplifier 104 in conjunction with a recorded image to be used by anoperator such as on an 81/2-by-11-inch page. Alternately, the system maybe used for microfilm reproduction wherein a high resolution image 1414is required and wherein image 1414 is very small for printing onmicrofilm. For this embodiment, illumination amplifier 104 may be largefor providing greater image resolution and post-optics 1436 may provideillumination image reduction capability to print or record a highresolution miniature image 1414 on microfilm.

In another embodiment, post-optics 1436 may include a scanner forscanning image 1435 onto screen or medium 1451. The scanner may be awell-known prior art electo-mechanical scanner such as used in Xeroxcopiers and OCR systems or may be the electro-optical scanner discussedin application Ser. No. 727,330 with reference to FIG. 12 therein and asfurther discussed herein. In this embodiment, the scanner may scan animage such as a rectangular image across screen or medium 1451 asdiscussed for the photoplotter with reference to FIGS. 8 and 10 in U.S.Pat. No. 3,986,022. Alternately, image 1435, 1437 from amplifier 104 maybe continuously changing as it is scanned across screen 1451 or medium130. For example, control signal 133 may control a sequence ofalpha-numeric characters which are scanned across a screen or medium1451 for displaying or recording alpha-numeric information, wherein eachscanned position may correspond to a different character commanded bysignal 133, as discussed with reference to FIG. 12B of application Ser.No. 727,330.

The TV system of the present invention includes many additionaladvantages implicit in the small size, simplicity, and projectionaspects. For example, this TV set may be used in a manner similar tocommon slide projectors and movie projectors wherein post-optics 1436may include zoom capability, screen 1451 may be a portable screen or awall and projector 1410-1412 may be a portable TV projector forprojecting colored TV pictures on various types of screens and walls.Post-optics 1436 may also include well-known focusing optics as iscommon in slide projectors for focusing image 1414 on screen 1451 toprovide projection from different distances and positions.

A high-intensity low-power portable embodiment of the TV system of thepresent invention may be provided, wherein source 100 constitutes thehigh-power dissipation element of the system and may be implemented as aflame-type lamp and wherein power-consuming electronics in projector1410 may be powered with batteries. Lamp 100 may be a gas lamp or otherlamp such as used on searchlight, lanterns, and in lighthouses toprovide high-intensity illumination without electrical powerconsumption. Integrated circuit electronics may be used to driveillumination amplifier 104, where typical illumination amplifiers suchas liquid crystals have bery low power dissipation and whereinintegrated circuit electronics do not need high voltage and high powereddrives usually required for conventional television sets and thereforemay be provided in a low-power battery-operated portable configuration.

Flexibility of the instant projection TV arrangement permits operationwith many different screens including a self-contained screen for closeviewing and a remote projection screen for audience-type viewing.Illumination intensity may be controlled such as a function of theviewing screen using pulse or amplitude modulation as signal 132 tosource 100 or signal 133 to illumination amplifier 104. Portable screensmay be used such as a removable self-contained screen for self-containedviewing and a remote screen such as a folding slide projector screen foraudience viewing. Use of both, a romovable self-contained screen and aportable remote screen, in conjunction with zoom and focusing capabilityin post-optics 1436 permits adaptation to many different viewingsituations.

In another embodiment, illumination amplifier 104 may be coupled toprovide illumination to an illumination sensitive medium such asphotographic film or a phosphorus screen using fiber optic techniquessuch as used on the Honeywell VISICORDER. Use of an illuminationdiffuser as a projection screen at the remote end of a fiber opticbundle permits high intensity illumination from a small image to enterthe source end of a fiber optic bundle, where divergence of the fiberoptic strands permits a larger image to be projected or conducted fromthe destination end of the fiber optic strands to a larger screen (oralternately a smaller screen) for display purposes.

One traffic control system has been described in U.S. Pat. No.3,986,022; wherein an alternate embodiment or additional features forthe said previously disclosed embodiment are discussed below. Theillumination amplifier projection arrangement discussed above may alsobe used for traffic control as a traffic light by projecting coloredsignals, alpha-numeric characters, symbols, and other information ontraffic control panels and display screens. This embodiment may use theambient illumination feedback, color control, projection control, andother features of the present invention as applied to traffic controlsystems.

The pictorial image feature of the present invention exemplified with aTV projection system may also be used for hardcopy recording ofpictorial information. For example, use of an illumination sensitivemedium 130 included in screen 1451 permits recording of pictorialinformation such as in a facsimile machine, a pictorial copier, or othersuch systems.

In the multi-beam embodiment, one beam may be used for operator viewingof a projected image and another beam may be used for recording of thatimage. For example, in a TV system used for projection viewing, it maybe desired to record an image. Therefore, an illumination amplifiershutter may be used to expose an illumination sensitive medium with analternate beam or with a redirected primary beam such as discussed forthe single-lens reflex camera with reference to FIG. 9 of U.S. Pat. No.3,986,022. Said reflex camera provides viewing to set up the picture andrecording to expose the illumination sensitive medium using a singledirectionally controlled image beam. Alternately, a plurality of beamsmay be provided for simultaneous viewing and recording. Therefore, inaccordance with this feature of the present invention, a system isprovided for viewing an image and for recording an image usingillumination amplifier devices such as a liquid crystal arrangement.

A plurality of controllable segments have been described relative tophotoplotter and camera-type systems with reference to FIGS. 8A-8C andfor a character display system such as with reference to FIG. 6 of U.S.Pat. No. 3,986,022 and further with reference to FIG. 12B of copendingapplication Ser. No. 727,330. In an alternate embodiment, these segmentillumination control arrangements may be implemented with the imagecontrol arrangement discussed for the image projection system such asfor TV receivers. For example, the resolution of the TV image controlsystem provides rectangular images at a very large number of anglesrelative to the 45-degree angular increments discussed with reference toFIG. 8A of U.S. Pat. No. 3,986,022 and may provide a very large numberof different types of characters for a character generator in additionto a common set of alpha-numeric characters. Further, aperture controlsuch as discussed with reference to FIGS. 8B and 8C of U.S. Pat. No.3,986,022 may be provided with significantly greater resolution by usinga large number of illumination amplifier segments compared to the threesegments shown in said FIGS. 8B and 8C.

Alternate Scanner Embodiment

An alternate scanner embodiment will now be discussed with reference toFIG. 12E. Illumination control device 1279 includes a plurality ofcontrolled surfaces 1270-1276 for controlling illumination signals1250-1256 respectively as controlled reflected signals 1260-1266respectively. Controlling of elements 1270-1276 to be selectivelyreflective causes illumination from source 110 to be selectively scannedwith signals 1260-1266 such as onto screen 1223. For example, generator1224 may generate illumination characters in response to illumination102 from source 100, 1225 which may be selectively reflected fromsurfaces 1260-1266 to scan the illumination characters onto screen 1223,as discussed with reference to FIG. 12E in copending application Ser.No. 727,330. For example, characters generated with generator 1224 alongincident beam 1250 may be reflected as signal 1260 if element 1270 isreflective and may not be reflected as signal 1260 if element 1270 isnot reflective. Similarly, incident illumination signals 1251-1256 maybe reflected or nonreflected from elements 1271-1276 respectively assignals 1261-1266 respectively depending upon whether elements 1271-1276are controlled to be reflective or nonreflective. Signals B0-B6 may beused to control elements 1270-1276 similar to the arrangement discussedwith reference to FIGS. 12A-12D in application Ser. No. 727,330 andother approaches may be used to control devices 1270-1276 similar tothat discussed for the other scanner embodiments.

The arrangement discussed with reference to FIG. 12E is shown insimplified form for ease of description. Elements 1270-1276 may be abatch fabricated device such as discussed with reference to FIG. 4 inU.S. Pat. No. 3,986,022 and may be formed as facets 1270-1276 or flatareas on spherical substrate 1279 which may be a glass substrate.Alternately, continuous control may be provided over the surface of asingle continuous circular or spherical surface providing differentreflecting angles using analog spacial methods of moving a reflectingarea over substrate 1279 similar to well-known prior art analog spacialarrangements. Alternately, elements 1270-1276 may be individual elementsthat are not batch fabricated which may be implemented with well-knownmethods such as liquid crystal methods wherein each device 1270-1276 mayhave an innermost electrode closest to the center of hemisphere 1279being reflective and being covered with liquid crystal material and mayhave an outermost transparent electrode for containing the liquidcrystal material between the inner reflective electrode and substrateand the outer transmissive electrode and cover as is well known in thereflective liquid crystal art for providing reflective mode operation.When the liquid crystal material is controlled to be opaque orscattering, illumination 1250-1256 may not be able to penetrate thereflecting electrodes and therefore may not be reflected but may bescattered. When the liquid crystal material of a device 1270-1276 iscontrolled to be transmissive, incident illumination 1250-1256respectively will be transmitted by the outermost transparent electrode,transmitted by the transparent liquid crystal material, reflected by thereflective innermost electrode back through the transparent liquidcrystal material and through the transparent outermost electrode asreflected signals 1260-1266 respectively. Therefore, the arrangementdiscussed with reference to FIG. 12E can be controlled to provide all ofthe capabilities discussed with reference to FIGS. 12A and 12B in saidcopending application Ser. No. 727,330.

Further, substrate 1279 may be spherical in shape with reflective facetslike the well-known devices used for a reflective effect such as inballrooms, but with the difference that the faceted mirrors havecontrollable reflectivity such as for controlled scanners, choppers, andother illumination control arrangements.

The arrangement shown in FIG. 12E is intended to be indicative of asolid-state version of a scanning mirror such as provided in Xeroxmachines and other scanning devices. In such devices, as the scanningmirror is rotated from an angle shown with element 1270 to an angleshown by element 1276 through angles shown by elements 1271-1275;illumination is reflected through the angles shown by illumination beams1260-1266 respectively. Therefore, the arrangement shown in FIG. 12Eprovides a solid-state electro-optical device for replacing prior artopto-mechanical scanning arrangements.

A scanner embodiment is described in referenced application Ser. No.727,330 with reference to FIG. 12B and FIG. 12C therein and withreference to FIG. 12E herein; wherein source 1225 illuminates generator1224 to provide an image to be scanned onto a screen with scannersegments 1230-1237 or 1260-1266 respectively. In an improved embodiment,segments 1230-1237 or 1260-1266 may be formed having alpha-numeric orother characters wherein the characters may be generated at surfaces1230-1237 or 1260-1266 rather than with a separate generator 1224. Ifeach of surfaces 1230-1237 or 1260-1266 contained image generationcapability such as controllable segments for alpha-numeric characters asis well known in the art, then control of the appropriate surface tohave selected segments reflective and for all other surfaces to betransmissive would project the appropriate segments and therefore thedesired characters onto screen 1223. In this embodiment, thecorresponding segment on each of surfaces 1230-1237 or 1260-1266 may beconnected together in parallel for selecting that corresponding segmenton all surfaces. Selection of the particular surface would be providedby selecting the appropriate one of eight return electrode signals B0-07(FIG. 12C) so that only the selected surface would have the segmentsreflective for display of the controlled character on screen 1223.

This arrangement is analogous to well-known display refresh electronics,where a particular character out of a plurality of characters isselected with individual character select signals and where all of thecorresponding segments of the plurality of characters are connected inparallel to a particular segment control signal. Therefore, coincidenceof a character select signal and the segment select signals define whichsegments of which character are to be displayed. Such an arrangement isdiscussed in detail in copending application Ser. No. 101,881 relativeto FIG. 2D and in copending application Ser. No. 288,247 relative toFIG. 4 therein showing character select control signals and segmentselect controls from select drivers and from segment driversrespectively for a segment display tube wherein said FIG. 2D and FIG. 4and the related discussion are herein incorporated-by-reference. Asimilar selection embodiment using liquid crystal type characters onangular surfaces shown in said FIG. 12B and FIG. 12E can be used toimplement the scanning of multiple characters onto a refreshable screen1223.

In another embodiment, generator 1224 may be constructed as an integralpart of scanner 1222; such as with another layer above surface 1230(FIG. 12C) wherein the projection image may be formed with integralgenerator 1224 and may be reflected to the correct position on screen1223 having a batch fabricated self-contained character generator andscanner arrangement.

In accordance with the projection display arrangement of the presentinvention, display arrangements 1220 and 1201 may be miniature displaysand screen 1223 may be a large screen, wherein post-optics 1436 (FIG.14) may be used to project and focus scanned images 1240-1247 or1260-1266 along screen 1223 (FIG. 12B and FIG. 12E) and onto screen 1451(FIG 14A).

A further important feature of the scanner and projector arrangements ofthe present invention includes the ability to scan high intensityillumination that is magnified to large dimensions such as withpre-optics 1433 or post-optics 1436 (FIG. 14A). For example, pre-optics1433 (FIG. 14A) may be inserted between source-generator 1224 andelectro-optical device 1222 and 1279 for focusting projected charactersformed with generator 1225 onto small controllable reflectors 1230-1237and 1270-1276 respectively for selectively scanning or controllingprojection of illumination from source 1225 and generator 1224. Focusingof illumination onto devices 1230-1237 and 1270-1276 forms a very smallbeam of illumination focused on devices 1230-1237 and 1270-1276 andreflected from devices 1230-1237 and 1270-1276 to project largemagnified images on a screen with a very small focused beam using verysmall-sized reflecting devices.

Spacial Control of Illumination

Spacial control of illumination is well known in the art using resistiveelectrodes for providing potential gradients. Another feature of thepresent invention provides such spacial control of illumination usingthickness of electro-optical material. For simplicity, this arrangementwill be discussed for liquid crystal material with reference to FIG. 15Aand FIG. 15B.

Liquid crystal material 1512 may be sandwiched between a pair of glasssubstrates 1510 and 1511 having electrodes 1513 and 1514 respectivelydeposited or otherwise placed thereon. A retainer 1515 for liquidcrystal material 1512 may be constructed with teflon and a sealer 1519may be constructed with epoxy. The arrangement show in FIG. 15Arepresents a cross section, wherein retainer 1515 and seal 1519encapsulate liquid crystal material 1512 in the vertical plane andsubstrates 1510 and 1511 encapsulate liquid crystal material 1512 in thevertical plane and substrates 1510 and 1511 encapsulate liquid crystalmaterial 1512 in the horizontal plane. In FIG. 15A, liquid crystalmaterial 1512 is shown deeper at the left-hand side and shallower at theright-hand side and is shown in FIG. 15B deeper in the center andshallower at the outer periphery implemented by properly dimensionedretainer 1515 and seal 1519 and may be further implemented withsubstrates 1510 and 1511 ground at sloping angles down to the left asshown in FIG. 15A and down toward the outer periphery as shown in FIG.15B. Excitation of liquid crystal material 1512 with the proper constantvoltage across electrodes 1513 and 1514 will cause the liquid crystalmaterial at the shallower right-hand portion of FIG. 15A and at theshallower outer periphery of FIG. 15B to become opaque and will preservethe transmissive nature of the liquid crystal material 1512 at thedeeper left-hand side of FIG. 15A and deeper central portion of FIG.15B. As the electrical field between electrodes 1513 and 1514 isincreased the liquid crystal opaque region interface at the shallowerright-hand portion shown in FIG. 15A will move towards the left and theliquid crystal opaque region interface at the shallower outer peripheryshown in FIG. 15B will move towards the center thereby encompassing agreater area. Conversely as the electric field is decreased, the liquidcrystal opaque region interface at the shallower right-hand portionshown in FIG. 15A will move towards the right and the liquid crystalopaque region interface at the shallower outer periphery shown in FIG.15B will move towards the outer periphery thereby encompassing a lesserarea. This variable depth method may be used in combination with thewell-known prior art method using resistive electrodes to obtain anadditional degree of freedom of control.

Spacial control is well known in the prior art such as controlling therelative transmissive and opaque areas of the liquid crystal device.These arrangement are inaccurate because of the difficulty incontrolling liquid crystal device thresholds, excitation voltages, andother characteristics. A feedback arrangement will now be discussed toprovide precise spacial control such as to control the relative areasthat are opaque and transmissive of a liquid crystal device. Use of theclosed loop feedback method of the present invention significantlyenhances precision of spacial control, as will now be discussed withreference to FIGS. 1 and 15A. The electro-optical arrangement shown inFIG. 15A may be illumination amplifier 104 shown in FIG. 1. Illumination102 from source 100 may illuminate amplifier 104 controlled with signal133 to generate controlled illumination 108 and 110. Feedback sensor 134generates feedback signal 114 in response to illumination 110, whereinsignal 114 is processed with signal processor 116 and command device 127and signal processor 128 for control of amplifier 104. Control may beanalog control or digital control and may be pulse modulated control orother forms of control discussed in U.S. Pat. No. 3,986,022 whereindigital excitation is discussed with reference to FIG. 2A, pulsemodulated excitation is discussed with reference to FIGS. 2B-2D andother forms of excitation are discussed elsewhere therein.

One embodiment of a feedback arrangement will now be discussed withreference to FIG. 15A as a multiple-loop spacial feedback controlarrangement, where this arrangement may also be used with otherembodiments such as discussed in U.S. Pat. No. 3,986,022 and applicationSer. No. 727,330 and elsewhere herein.

Source 100 illuminates amplifier 104 with source illumination 102 togenerate controlled illumination 110 comprising signals 110A, 110B, and110C. Illumination 110 exposes sensors 134 comprising AGC control sensor134A and spacial control sensor 134B to generate feedback signals 114comprising AGC feedback signal 114A and spacial control feedback signal114B to be compared with command signals 126 comprising a scale factoror AGC command signal 126A and a spacial command signal 126B to feedbacksignal processors 116, 128 to generate control signal 132 andillumination amplifier control signal 133. This arrangement is exemplaryof a multiple-feedback arrangement such as for AGC and spacial controland is also exemplary of other multiple feedback arrangements usablewith other embodiments discussed herein; in U.S. Pat. No. 3,986,022; andin copending application Ser. No. 727,330. Source 100 may generateillumination 102 in response to feedback signal 114 where source controlis exemplary of automatic gain control and wherein other arrangementsmay be used such as control of an electro-optical device 104 to controlsource illumination. Illumination 102 is controlled by illuminationamplifier 104 such as having liquid crystal material 1512 in a spacialcontrol. The transmissive region of the spacially controlled material isshown in the right-hand portion of FIG. 15A wherein the thicker theliquid crystal material the more likely it is to be transmissive andwherein the thickest spacial region is the last region to become opaque,as discussed above. Therefore, sensor 134A providing a form of automaticgain control (AGC) may be placed in a region that is the least likelyregion to become non-transmissive or alternately may be placed todirectly sense source illumination 102 for AGC. AGC illumination 110Amay be sensed with sensor 134A to generate feedback signal 114A whichmay be compared with command signal 126A using processor 116, 128 togenerate control signal 132 to control source 100.

Similarly, spacial illumination control may be provided with feedbackarrangement 1502 where source illumination 102 as controlled byillumination amplifier 104 may be received as controlled illumination110B, processed with post-optics 1436 to generate post-processedillumination 110C for illuminating sensor 134B. Sensor signal 114B maybe processed with processor 116, 128 to generate illumination amplifiercontrol signal 133 for controlling illumination amplifier 104.Post-optics 1436 may include an accumulating lens for accumulating aportion of or all of the illumination from illumination amplifier 104 toprovide spacial control of amplifier 104.

Processor 116, 128 may compare feedback signal 114B with command signal126B to generate a difference signal 133 to provide spacial control tomake a particular area proportional to command signal 126B opaque ortransmissive. For example, if command signal 126B is at one-quarter ofthe peak amplitude; processor 116, 128 may generate command signal 133to servo the amplifier 104 to make three-quarters of the area opaque andone-quarter of the area transmissive to generate feedback signal 114Bbeing one-quarter amplitude. When command signal 126B and feedbacksignal 114B are each related to one-quarter illumination amplifiermagnitude, the difference signal 133 will maintain illuminationamplifier 104 having that particular excitation level and that spacialillumination control level. Therefore, the amplitude on command signal126B defines the relative areas of amplifier 104 that are opaque andtransmissive.

Spacial control used to form lines, circles, segments, and otherconstant area devices are well known in the art by providing positiveand negative excitation to resistive electrodes wherein the transitionthrough zero voltage gradient provides the desired line or other shapedelement. Biasing of the constant gradient is used to control theposition of the transmissive element. The prior art does not controldimensions nor characteristics of the transmissive or opaque elementexcept as fixed in the design of the device. An arrangement will now bediscussed, to control the characteristics of the element in addition tothe prior art methods of providing spacial control.

Biasing of the constant slope gradient is used in the prior art toprovide spacial control. In accordance with the present feature of thepresent invention, the slope of the gradient may be controlled tocontrol the spacial distance covered by the line or other element, tocontrol the sharpness and other characteristics of the edges, and toprovide other such capabilities. Such gradient slope control may beprovided with an illumination feedback loop in the form discussed withreference to FIG. 15A herein. For example, control of an element such asa line or circular arc may be provided with feedback loop comprisingpost-opitcs 1436 to accumulate the illumination as illumination signal110C, sensor 134B for generating feedback signal 114B proportional toillumination signal 110C, processor 116, 128 for processing feedbacksignal 114B and for comparing feedback signal 114B with command signal126B to generate illumination amplifier control signal 133 to controlillumination amplifier 104. Command signal 126B may define the amount ofillumination to be transmitted by amplifier 104 and may be used tochange the gradient of the electrode voltage on amplifier 104 such as byincreasing the positive excitation and decreasing the negativeexcitation such as with push-pull or inverter amplifier techniques. Thisgradient slope control may change the shape of the transmissive elementand the edgequity or sharpness of the edges.

Further, a plurality of feedback loops may be provided such as for shapecontrol of the illumination element, spacial position control of theillumination element, and control of other such characteristics.Further, the system may operate in a reflective mode wherein the moreremote electrode 1514 may be reflective for reflecting illumination 102in contrast to the transmission of illumination 102 shown in FIG. 15Aand wherein sensors 134 may sense reflected illumination.

One embodiment of the spacial control feature of the present inventionis a spacial controlled clock such as a watch 1520 (FIG. 15C). Liquidcrystal watches are well known in the art such as providing digitaldisplays 1521. The liquid crystal watch of the present invention usesarea control to provide analog rotational motion similar to mechanicalwatches with second, minute, and hour hands. Because the angularposition of a display element may be controlled with spacial controlgradient methods, these elements may be used to provide pointers on awatch. For example, controlled illumination area 1522 may represent anhour pointer which may traverse the periphery of watch 1520 once every12 hours and illumination pointer 1524 may be a minute pointer and maytraverse the periphery of watch 1520 once every hour and further otherpointers may provide second information and date informationaccordingly. The position of these pointers 1522 and 1524 may becontrolled with digital electronics used to generate digital displays1521 which are well known in the art. These digital electronics mayexcite digital-to-analog converters 1227 to control the gradient byexciting resistive electrodes to control the position of pointerelements 1522 and 1524. The analog spacial control pointers of watch1520 may be used in conjunction with digital display 1521 or inreplacement thereof.

An alternate embodiment is shown in FIG. 15B where a circular symmetryspacial control arrangement is provided. Illumination amplifier 104 isshown in section circular symetry form having feedback servo 1502generating feedback control signal 133 in response to controlledillumination 110B similar to that discussed with reference to FIG. 15A.Feedback servo 1502 may have post-optics 1436 for generating apost-processed illumination signal 110C to illuminate sensor 134B forgenerating feedback signal 114B to be compared with command signal 126B.Processor 116, 128 may compare feedback signal 114B with command signal126B to generate feedback control signal 133 to control illuminationamplifier 104. Illumination amplifier 104 may comprise glass substrates1510 and 1511, electrodes 1513 and 1514 on substrates 1510 and 1511respectively, spacer and support 1515, sealer 1519, and liquid crystalmaterial 1512.

Substrates 1510 and 1511 may be formed to provide thicker liquid crystalmaterial at the center and shallower liquid crystal material at theouter periphery as shown in FIG. 15B. Therefore, excitation 133 controlsthe liquid crystal material at the outer periphery to become opaquebefore the center liquid crystal material becomes opaque. As excitationis applied and increased in magnitude, liquid crystal material at theouter periphery near spacer 1515 becomes opaque but the liquid crystalmaterial towards the center remains transparent. As the excitation isincreased, the outer periphery of opaque material increases in arearadially inward towards the center until a level of excitation isreached sufficient to make the deeper liquid crystal material at thecenter opaque. Therefore, the arrangement shown in FIG. 15C may be usedto electronically control the radius of the central transparent area1505.

Alternately, substrates 1510 and 1511 and spacer 1515 may be formed toprovide thicker liquid crystal material at the outer periphery andshallower liquid crystal material at the center to provide a transparentcircle at the outer periphery that increases in radius away from thecenter as excitation is increased, providing the complement of operationof the arrangement shown in FIG. 14B. Further, the arrangement shown inFIG. 15B may use the high resistance electrode arrangement or othertechniques to provide electric field gradients to generate a transparent(or opaque) spot 1505 and to control the radius of spot 1505 forillumination control.

The arrangement discussed with reference to FIG. 15B may be used as acamera shutter and aperture such as discussed with reference to FIGS.8-10 in U.S. Pat. No. 3,986,022 and copending application Ser. No.727,330. A command signal 126B may be input to feedback servo 1502 (FIG.15B) to generate control signal 133.

If command signal 126B is a large command signal, servo 1502 generates alarge excitation signal 133 which causes the complete area of liquidcrystal material 1512 to become opaque and spot 1505 to reduce to zeroradius of transparent material; thereby blocking all of illumination 102and implementing a shutter. This shutter may be used in conjunction withmechanical shutters and other photographic camera devices as discussedwith reference to FIGS. 8-10 of U.S. Pat. No. 3,986,022. Changing ofcontrol signal 126B to a command magnitude less than the thresholdmagnitude for the thicker center liquid crystal material causestransparent spot 1505 to form having a radius that is a function of themagnitude of command signal 126B.

Control of transparent spot 1505 is similar to control of an aperturesuch as a prior art mechanical aperture for controlling the amount ofillumination transmitted. Therefore, a camera using the arrangementshown in FIG. 15B controls exposure of an illumination sensitive medium130 by initially maintaining shutter aperture arrangement 104 opaquewith a high magnitude command signal 126B and then generating said lowermagnitude threshold signal 126B in response to an exposure commandsignal to provide a transparent spot 1505 having a desired radius thatis a function of an aperture or illumination magnitude camera setting.After a particular exposure time, signal 126B is returned to the highmagnitude value to again control illumination amplifier 104 to be fullyopaque to terminate the exposure. The shutter magnitude may be acharacteristic of the camera system such as a fixed high magnitude leveland the exposure magnitude may be settable such as with a well-knownpotentiometer setting to control the aperture to define the thresholdmagnitude of signal 126B to control the radius of transparent spot 1505with feedback signal 133 for the duration of the exposure. Well-knownprior art timing arrangements may provide timing for the exposure inresponse to an exposure command from an operator, switching to the lowermagnitude exposure signal in response to the exposure command and thenswitching command signal 126B back to the higher magnitude shuttersignal after the time delay for exposure has expired.

The arrangement discussed with reference to FIG. 15B may operate as aconventional aperture in an open loop command arrangement or may operateas an adaptive aperture for the closed loop control arrangement shown inFIG. 15B. For example, generation of control signal 133 in response tocommand signal 126B causes a controlled diameter of transparent spot1505. Use of feedback servo 1502 operating in response to illumination110B causes the diameter of transparent spot 1505 to be controlled to amagnitude that is a function of the command signal 126B and the mgnitudeof incident illumination 102. Therefore, the greater the command signal126B the larger will be the diameter of transparent spot 1505 and thegreater the magnitude of incident illumination 102 the smaller will bethe diameter of transparent spot 1505 implicit in the operation of servo1502.

A camera control system will now be discussed with reference to FIG.15D. For simplicity of illustration, a Texas Instruments 74122 timedelay multivibrator and a Fairchild 709 operational amplifier will beused to exemplify this invention, although many other controlarrangements may be provided. Multivibrator 1530 generates output pulsesQ and Q in response to closure of switch 1531 to excite input A1, whereswitch 1531 initiates an exposure. The width of output pulse Q isdetermined by the values of capacitor CE and resistor RT tomultivibrator terminals C and R/C. Resistor RT may be a variableresistor for controlling time duration of output pulse Q, where resistorRT controls exposure time. The exposure may be interlocked with manydifferent signals using inputs B1 and B2 and using other signals ANDedor ORed together using well-known logical techniques. For example, aswitch may be closed by the film being wound after an exposure and thisswitch closure may enable the next exposure through input B1 and abattery having sufficient charge for the exposure such as to drive aflashbulb or for operation of the camera electronics may interlock theexposure with a signal input to terminal B2. Many other interlocks maybe provided hereto. Exposure control pulse Q may be processed withconventional electronics such as with operational amplifier 1532exemplified by the Fairchild 709 or 741 amplifiers. The amplitude ofoutput pulse 126B may be controlled with variable input resistor RI anda variable feedback resistor RF to establish gain of amplifier 1532 andtherefore to establish amplitude of output pulse 126B. Further, variableresistor RB may bias output pulse 126B to a desired level. The inputsignals to amplifier 1532 may be connected to the negative inputterminal as shown in FIG. 15D or conversely may be connected to apositive input terminal using well-known differential amplifiertechniques.

Control potentiometers RI, RF, and RB may control the aperture function;where the amplitude and bias of signal 126B to feedback servo 1502 maycontrol excitation signal 133 and therefore control the radius oftransparent area 1505 (FIG. 15C). For example, the bias signalcontrolled with resistor RB may define the steady state excitationmagnitude of signal 126B which may be adjusted to cause transparent area1505 to have zero radius or to cause illumination amplifier 104 to befully opaque to provide the shutter function in the absence of a pulse Qfrom multivibrator 1530. Control potentiameters RI and RF may be used tocontrol amplitude of control pulse 126B, wherein the amplitude of pulse126B controls the radius of transparent area 1505 and therefore controlsthe function of an aperture control illumination amplifier 104 for acamera system. It should be recognized that there may be interactionbetween the bias controls and amplitude controls relative to aperturesize. Therefore, control RB may be a factory setting, control RI may bea factory setting, and control RF may be an operator-determined aperturecontrol setting.

Multivibrator 1530 may be relatively insensitive to false triggeringsuch as jitter or bounce of switch 1531 and the output of multivibrator1530 may be independent of further transitions of the inputs once firedand may be a function only of timing components CE and RT, wherewell-known circuits for switch debounce may not be necessary.

The Ser. No. 74122 multivibrator may be adjusted from a 40-nanosecond toa 28-second exposure time and may be further extended in exposure timeby proper selection of components CE and RT. It may be desirable tolimit the exposure time delay to a minimum of one millisecond ratherthan the 40-nanosecond time, which can be provided with fixed series andparallel resistors connected between terminals C and R/C and connectedwith components CE and RT in well-known parallel and serialcombinations. The output pulse may be terminated such as with feedbacksignals 132 and 133 or other signals such as integration signals 956 and120 as discussed with reference to FIG. 9C in U.S. Pat. No. 3,986,022;where a threshold comparitor circuit such as the Fairchild 710 maydetect a desired threshold amplitude and generate a clear signal.Alternately, the Ser. No. 74122 multivibrator has a retriggerablecapability wherein well-known circuits may be provided for retriggeringmultivibrator 1530 to generate longer output pulses Q and Q. Suchmultivibrators are discussed in the TTL Data Book For Design Engineersby Texas Instruments Inc, copyright 1973; particularly at pages 82 and134-140 therein and herein incorporated-by-reference.

Audience Display System, Additional Features

An audience display system has been described in U.S. Pat. No. 3,986,022wherein improvements thereto are presented hereinafter.

An audience display system implemented in a transmissive mode such asbeing back-lighted with floodlights is enhanced if the floodlightillumination is evenly dispersed over the display area. Therefore,another inventive feature is related to including a device for evenlydispersing illumination over an audience display arrangement inparticular and over an electro-optical device in general. Practicalsystems provide relatively even distribution, but it should berecognized that perfection in uniformity of distribution may not bepractically achievable. Therefore, it is herein intended that termsrelating to uniform distribution mean good distribution of illumination.In one embodiment, use of floodlight type devices or other wide beamdevice provides good distribution of illumination. In a further improvedembodiment, an illumination distribution device may be placed inbetweenthe illumination source and the electro-signal device such as a screenfor illumination distribution that may be composed of frosted glass,lucite, or other illumination conducting and distributing devices.

Various features of the present invention may be used in an environmentthat has changing ambient light conditions such as for an outdoordisplay that may operate in an outdoor environment having daytime andnighttime conditions and further having varying sunlight conditions inthe daytime. As discussed in U.S. Pat. No. 3,986,022; an electro-opticaldevice may operate with ambient illumination (not artificialillumination) when ambient illumination such as sunlight is sufficientlyintense. When ambient illumination is not sufficiently intense, theelectro-optical device may operate in conjunction with artificialillumination such as with floodlights. An electronic control may controlartificial illumination as a function of natural illumination. Forexample, in the simplest implementation a manual switch may be providedto turn-on the artificial illumination when the natural illumination isnot sufficiently intense. Alternately, an automatic system amy beimplemented such as with a photosensor detecting ambient illuminationand controlling the intensity of artificial illumination. Thisembodiment may be better understood with reference to FIG. 1 asdiscussed below.

Photosensor 134 may sense ambient illumination and generate feedbacksignals 114, 120, 124, and 139 with feedback signal processors 116 asfeedback to command device 127 and signal processor 128 for controllingintensity of source 100, which may be a floodlight, as a function ofambient illumination. Similarly, amplifier 104 may be controlled as afunction of ambient illumination with signal 133. Alternately, feedbacktransducer 134 may sense transmitted and/or reflected illumination 110from amplifier 104 for controlling illumination amplifier 104 tomaintain a desired intensity of signal 110 comprising either naturalillumination, source illumination, or a combination of natural andsource illumination.

In a further improvement, an audience display system may include aplurality of illumination sensors including an ambient illuminationsensor and a controlled illumination sensor. The ambient illuminationsensor may sense ambient illumination 110 to control source 100 withfeedback signals 120 and 124 to processor 128 to generate source controlsignal 132. The control illumination sensor may sense controlledillumination 110 to control amplifier 104 with feedback signals 120 and124 to processor 128 to generate amplifier control signal 133.

In the above-described control arrangements, command elements 127 and128 may include a stored program digital computer, as discussed in thereferenced copending patent applications, wherein this computer mayinclude a program to optimize intensity as a function of ambientillumination by controlling source 100 and illumination amplifier 104 toprovide the desired optical effect. In this embodiment, computer 251would receive feedback signals from sensor 134 comprising an ambientillumination sensor and a controlled illumination sensor for generatingcontrol signals 132 and 133 in response to an interrelationship betweenambient and controlled illumination intensity.

Ambient illumination is herein intended to mean external illumination inthe environment of the controlled device, background illumination, andgenerally external illumination that is not controllable in response tothe illumination feedback signal and which may be controlled with theillumination amplifier arrangement of the present invention.

The audience display features of the present invention have beendiscussed with reference to a preferred embodiment using anelectro-optical arrangement but the improvements are also applicable toother embodiments. For example, the improvements of feedback control,ambient illumination control, intensity control using pulsed widthmodulation, colored displays, and other inventive features may be usedin conjunction with incandescent bulb displays and other displays,wherein it is intended that the features of the instant invention, notbe limited to an electro-optical embodiment.

Further Considerations

The system of the present invention is directed to illumination controlin a general and a broad conceptual form. For simplicity of discussion,illumination control devices have been characterized as illuminationamplifiers, liquid crystal devices, electro-chemical devices,electro-optical devices, and many other well-known devices have beenreferred to in general form. These generally referred to well-knwondevices include electrochromic devices, electrophoretic devices, PLZTdevices, and other devices for illumination control.

Control of transmissivity and reflectivity is discussed and claimed inthe system of the present invention for devices such as liquid crystaldevices, where the device may be either transparent or opaque but maynot provide true reflectivity. As is well known in the art, thetransmissivity characteristic provides for control of transmission ofillumination by controlling the device to be transmissive or opaque.When operating in the reflective mode, a reflector may be provided toreflect illumination back through transmissive segments such as areflective rear electrode for reflecting illumination transmittedthrough the transmissive liquid crystal material. Therefore, althoughreflectivity may be discussed in the context of reflective liquidcrystals, etc, it is intended that the common reflective modeterminology pertaining to providing a reflector for reflective modeoperation imply an auxiliary reflector if the illumination controldevice itself does not provide such reflective characteristics.Certainly, if the controllable material such as liquid crystal materialprovides directly controllable reflectivity, there may be no need forauxiliary reflecting structures.

It is herein recognized that extremely high intensity illumination mayaffect certain electro-optical and electro-chemical devices in achemical or thermal manner that may be considered undesirable. For mostintensities and for most materials, this may not be a problem. For veryhigh intensities and for certain materials, the affect of energy levelsadversely affecting the electro-optical devices must be considered andthis consideration is herein recognized.

It is herein intended that the various inventive features set forthherein be usable in well-known illumination processing devices. Forexample, various inventive features including apertures, shutters,choppers, scanners, feedback control, etc. may be usable with well-knowntelescopes, microscopes, binoculars, and periscopes, and otherillumination processing devices.

Electro-Optical Thermal Design

In accordance with another feature of the present invention, anarrangement is provided for removal of thermal energy from anillumination amplifier device, which may constitute removal ofrelatively large quantities of thermal energy. For example, projectionarrangements illuminated with high intensity illumination may cause anillumination amplifier to absorb illumination energy to the degree wherethermal considerations become important, wherein heat transfer methodsdisclosed herein and/or well known in the art may be used.

An illumination amplifier may be illuminated with high intensityillumination and may exhibit a thermal temperature rise in response toabsorbed illumination energy. Some heat transfer may be provided throughpassive mechanisms inherent in substantially any implementation such asthrough radiation and through convection, but these inherent passivecooling mechanisms may not be sufficient. Therefore, supplementarycooling methods may be required. Many supplementary cooling methods aredisclosed herein and/or are well known in the art. For example, forcedair convection can be used such as with a fan blowing air over thesurface of the illumination amplifier. Also, a heat exchanger can beused either independently or in combination with other methods such asin conjunction with forced air cooling and/or in conjunction with fluidcooling. Forced air cooling can be provided with a well-known blower.Fluid cooling can be provided by circulating cooling fluid through aheat exchanger. Commercially available cooling elements can be used suchas commercially available fans; heat exchangers; fluid coolingarrangements such as chilled water, nitrogen, freon, air, or othercooling fluids or gases; and other cooling arrangements. Also, aradiation median such as a cool radiation receiver can be provided forradiant cooling of the illumination amplifier. Many other methods willbecome obvious from the teachings herein.

Thermal design is well known in the art and may be applied to thearrangement of the present invention from the teachings herein. This isexemplified with the articles by McNeal and Gordon and by Leonard andAxelband referenced herein and with multitudes of textbooks, articles,and other publications in the public domain.

Controls for heat transfer devices are well known in the art and mayinclude electronic, mechanical, and/or other control devices. Forexample, mechanical controls are well known for automobile coolingsystems and for household refrigerators, electro-mechanical controls arewell known for air conditioners and for household heating systems,electronic controls are well known for ovens, and many different typesof controls are well known for many applications. In view of the above,well-known thermal controls may be used with the embodiments set forthherein and therefore may not be further discussed herein for aparticular embodiment; but are intended to be implicit herein as willbecome obvious from the teachings herein.

Prior art systems using illumination amplifier devices are not concernedwith heat generated by the illumination amplifier device (IAD) becauseof the low illumination power levels used in prior art systems. Forexample, prior art liquid crystal devices (LCDs) are inherently lowpower devices and therefore with prior art systems there has been noconcern for heating due to electrical excitation. Further, prior artLCDs operate in relatively low intensity illumination environments suchas in sunlight or with low intensity illumination sources for nighttimeviewing such as provided with well-known LCD watch displays. Therefore,the prior art is not concerned with thermal effects of the incidentillumination or of the electrical excitation.

LCDs are affected by ambient temperatures, wherein the response isslowed at low temperature and the display is degraded at hightemperatures. Ambient temperature operation is considered by the priorart to be a requirement, wherein thermal considerations are limited tomerely placing a constraint on the operating environment. For example,LCDs are specified for operating in a limited ambient temperatureenvironment such as from 0° C. to 70° C. The prior art does not in anyway provide arrangements for cooling LCDs or other IADs because theprior art does not use LCDs in arrangements that might providesignificant heating effects or in arrangements that operate atenvironmental temperatures outside of the specified LCD operatingregions.

In accordance with the instant feature of the present invention, athermal control arrangement is provided to permit IADs to tolerate highenergy illumination and/or excitation and/or to operate in ambienttemperature enrivonments outside of the specified operating region forIADs. The need for such thermal control arrangements has not beenacknowledged by the prior art because the prior art is unaware of usesthat could exceed the thermal specifications of the IAD and/or extendthe use of IADs beyond the specified operating region. For example, inaccordance with the projection display arrangement of the presentinvention, an IAD can be illuminated with high intensity illuminationfor projection of high intensity large screen displays. High intensityillumination causes heating of the IAD and therefore could requirethermal design considerations. Because the prior art does not considersuch projection display arrangements, the prior art has not beenconcerned with high intensity illumination nor any need to cool an IADexposed to high intensity illumination.

For simplicity of discussion, the thermal design feature of the presentinvention will be discussed for a liquid crystal device (LDC). It isherein intended that any reference to an LCD be interpreted as areference to a generalized illumination amplifier device.

In a preferred embodiment, a projection IAD is provided, operating in areflective mode, having heat transfer devices as discussed hereinafter,and being illuminated by high intensity illumination. The prior art doesnot consider heat transfer devices, nor projection arrangements for IADsand certainly not in combination with reflective mode operation.

Although the preferred embodiment of a heat transfer device is relatedto cooling of an IAD, it will become obvious from the teachings hereinthat a heating arrangement for heating an IAD can be implementedtherefrom. Therefore, it is herein intended that any reference to heattransfer, cooling, etc be interpreted as a reference to a generalizedheat transfer arrangement for cooling, heating, etc.

Further, heat transfer means and methods are discussed herein fordifferent preferred embodiments, wherein it is herein intended that anyheat transfer arrangement discussed herein may be used in combinationwith any other heat transfer arrangement and with any IAD arrangement.

Yet further, heat transfer advantages are discussed herein for IAD, LCD,and filter arrangements; wherein it is herein intended that thisreflective mode heat transfer arrangement be applicable to illuminationdevices in general including lens, filters, etc as exemplified by IAD,LCD, and filter arrangements herein.

Heat transfer can be provided in the form of radiant, convective, and/orconductive heat transfer and can be enhanced with devices that improveradiation, convection, and conduction.

An IAD can be operated in a transmissive mode or in a reflective mode,wherein heat transfer arrangements for a transmissive mode IAD has moreconstraints than for a reflective mode IAD. For a transmissive mode IAD,both sides of the IAD are unobstructed to permit transmission of theillumination from one side to the other side. For a reflective mode IAD,illumination is reflected from the same side that is illuminated withthe incident illumination. Therefore, the back side or rear side(opposite from the illuminated side) of a reflective mode IAD isavailable for heat transfer devices. This provides a significantadvantage over transmissive mode arrangements because heating affectsdue to high intensity illumination are concentrated on the illuminatedportions of the IAD, wherein heat transfer from the back side of the IADis therefore significantly more efficient.

For transmissive mode IAD, both the front and the back of the IAD mustbe relatively transparent to illumination, thereby minimizing thelocation of thermal devices. For a reflective mode IAD, the back of theIAD does not have to be transparent and therefore can provide convenientmounting for heat transfer devices. Mounting of heat transfer devices onthe back of a reflective mode IAD brings the heat transfer device intovery close proximity with the illuminated front face of the IAD. Becausethe front face of the IAD typically exhibits the worst case heatingcondition, such a reflective mode rear cooled IAD permits a moreefficient thermal design. Therefore, in a preferred embodiment, areflective mode IAD is provided having a heat transfer arrangementmounted on the rear or back side of the IAD to enhance heat transfer.

Experience indicates that providing heat transfer from the back side ofa reflective mode IAD is about ten times better than providing heattransfer from the edges or outside periphery of an IAD, wherein such anorder of magnitude improvement is very significant.

Natural radiation, convection, and conduction provide some cooling forIADs, but such heat transfer may not be adequate for many uses. Forexample, substantially any device transfers radiant energy to or fromthe external environment and provides some heat transfer due to free airconvection and due to conduction through a mounting structure or othercontact structure. Such heat transfer may be significantly enhanced wihthe proper heat transfer devices.

One method of heat transfer is to provide forced conduction cooling suchas by blowing air at the IAD for cooling. This arrangement hasadvantages, wherein cooling air is transparent to illumination andtherefore can be directed at the front face of the IAD or at hot spotson the IAD for optimum cooling. Further, forced air cooling isinexpensive and effective for many applications. Disadvantages includethe primary disadvantage that it may be undesirable to provide a fan orother such device in many types of systems such as small portablesystems characterized by a calculator or an electronic toy. Further, ablower consumes a relatively large amount of electrical energy comparedto the excitation energy for an IAD, thereby degrading battery life forportable battery operated systems. Yet further, blowers havedisadvantages such as requiring dust filters, ducting, etc. In view ofthe above, a blower heat transfer device is acceptable for many IADapplications, but a conductive heat transfer device provides importantadvantages for other IAD applications.

Although an IAD is herein intended to be generally interpreted in abroad context, an illumination amplifier may be exemplified with an LCDin a preferred embodiment to provide a simple illustration of thefeatures of the present invention. Various arrangements of the heattransfer arrangement for illumination amplifiers will now be discussedin the embodiment of an LCD arrangement with reference to FIG. 16, whichis herein intended to be exemplary of the broad scope of illuminationamplifier arrangements.

Various embodiments of cooling arrangements are shown in FIGS. 16A-16D.These arrangements show LCD 1610 being illuminated by incidentillumination 1611 which is transmitted as transmitted illumination 1612and/or reflected as reflected illumination 1613. LCD 1610 may be heatedsuch as by absorbing incident illumination 1611, by heat dissipation dueto electrical excitation, by ambient conditions, etc. Inherent coolingis provided by radiation 1615 such as to the external environment,convection 1616 such as to the air, and/or conduction 1617 such as to amounting structure.

Forced air cooling can be provided with blower 1618 generating forcedair 1619 to cool LCD 1610. Blower 1618 can be any well-known blowerincluding fans, etc and can include devices such as plenums, tubing, etcto facilitate cooling.

Conductive cooling can be provided as shown in FIGS. 16B-16D. Conductivedevices 1621 and 1622 (FIG. 16B) and/or device 1623 (FIG. 16C) and/ordevice 1624 (FIG. 16D) can be placed in contact with LCD 1610 havingedge 1620, illustrated to provide an isometric perspective. Conductivedevices 1621-1624 can be placed in contact with LCD 1610 in a mannerthat provides good thermal contact such as by providing flat contactsurfaces, thermal conducting adhesives, thermal conducting contactmaterials, thin contact materials and/or various well-known thermalcontacting methods and devices. Conducting devices can be providedaround the periphery of LCD 1610 such as "picture-frame" type devices1621 and 1622 (FIG. 16B) and/or edge type devices 1623 (FIG. 16C). Suchpicture-frame and edge devices permit transmission of illumination 1611through a portion of the center of LCD 1610 to provide transmittedilluminaton 1612. Such devices can be mounted near the edge of LCD 1610for minimum obstruction of incident illumination 1611, such as shownwith conducting devices 1622 (FIG. 16B) and 1623 (FIG. 16C) oralternately such conducting devices can be mounted on the side of LCD1610 opposite the side receiving incident illumination 1611 such asillustrated with conducting device 1621 (FIG. 16B).

The arrangements shown in FIGS. 16A-16C can be used with transmissive orreflective mode LCDs, wherein the back side of LCD 1610 (the sideopposite the side illuminated with incident illumination 1611) is notobscured with heat transfer devices thereby permitting transmissive modeoperation.

In accordance with a preferred embodiment of the present invention, areflective mode IAD is provided having improved heat transfercapability, as will be discussed with reference to FIG. 16D. LCD 1610can operate in a reflective mode having controlled reflection ofincident illumination 1611 as reflected illumination 1613. Because ofthe reflective mode of operation, transmission of incident illumination1611 through LCD 1610 and through the back side of LCD 1610 is notrequired. Therefore, the back side of LCD 1610 is available for heattransfer devices. Because the thickness of edge 1620 of LCD 1610 issmall relative to the dimensions of the planer faces, heat transfer tothe back side is significantly more efficient than heat transfer to theedges. This can be seen in FIGS. 16B and 16C, where illuminationincident upon the center of LCD 1610 is conducted by LCD 1610 to theouter edges to be conducted away with conduction devices 1621-1623.Conversely, with the arrangement shown in FIG. 16D, heat need only beconducted through the relatively thin LCD 1610 to the back side to beconducted away with conduction device 1624. For prior art LCDs, thethickness may only be ten percent or may be only one percent of the facedimensions, thereby providing possibly a factor of 10 to 100 timesimprovement in heat transfer capability from the back side. Therefore,for many applications where heat transfer efficiency is important suchas for high intensity illumination for projection displays or wheresimple conduction without forced air or exotic cooling methods isimportant such as for hand-held calculators and electronic games, thearrangement shown in FIG. 6D represents a preferred embodiment havingsignificant advantages over other arrangements.

Conduction devices 1621-1624 can be simple thermal conduction devicessuch as metal devices or can be heat sinks, fluid cooling devices,thermoelectric coolers, or other known cooling arrangements. Heat sinkssuch as finned heat sinks are manufactured by many companies such as theVemaline Division of Astby and Barton Co. of Warwick R.I. and WakefieldEngineering Inc. of Wakefield MA. Thermoelectric coolers such as Peltiercoolers are manufactured by many companies such as Melcore of TrentonN.J. (FRIGICHIP and FRIGITOTE) and Frigidheat (Model 45M-10X). Severalconduction devices will now be discussed, which are exemplary of themore general conduction arrangements of the present invention.

Conduction devices 1621-1624 can be heat conductive mounting structuresthat conduct heat away from LCD 1610. Such devices can be heat sinksthat absorb heat energy or that conduct heat energy away from LCD 1610for better heat transfer. In one embodiment, heat conductive devices areconnected to the case or other structure of a display arrangement forheat transfer from the case to the air through free air convection. Inanother embodiment, conduction devices are known heat sinks such ashaving fins and other structures for efficient heat transfer to the airthrough convection. In another embodiment, a blower is used to improveheat transfer from the heat conduction device to the air. In yet anotherembodiment, cooling fluid is circulated through the heat conductivedevice to conduct heat away from LCD 1610. For example, forced air 1619from blower 1618 (FIG. 16A) can be blown into or through heat conductivedevices 1621-1624 as illustrated with arrow 1625. Alternately, arrow1625 can exemplify cooling fluid such as freon. Further, heat conductivedevices 1621-1624 can have fins or other arrangements for efficient heattransfer.

Several heat transfer arrangements are shown in FIG. 16E that can beused for heat transfer devices 1621-1624 (FIGS. 16B-16D). Heat transferdevices 1621-1624 can be heat sinks having fins 1626 for heatconduction, heat sinking, heat transfer to the air, etc. Heat transfercan be enhanced with blower 1618 generating forced air 1619. Heattransfer can be enhanced with cooling fluid flow such as with coolingtube 1628 having coolant 1627 entering and coolant 1629 exiting such aswith well-known coolant devices. One well-known cooling fluid device isan automobile radiator. Another well-known cooling fluid device is acommon household refrigerator or air conditioner having cold freon orother coolant circulated through cooling coils. Cooling coils 1628 canbe used in combination with heat sink 1626 to further improve coolingsuch as with an automobile radiator, a refrigerator, and an airconditioner.

Cooling can be provided with thermoelectric coolers, where elements1621-1624 can be thermoelectric coolers mounted or bonded directly toLCD 1610. Alternately, a thermoelectric cooler can be used for coolingheat sink material which conducts heat from LCD 1610 to thethermoelectric cooler, shown with heat sinks 1621-1624. Other coolingarrangements that can be used include dewars, conventionalrefrigerators, Peltier coolers, and other known cooling devices.

In an alternate embodiment, electro-optic material in IAD 1610 can becirculated through a coolant device such as a refrigerator, heatexchanger, etc for cooling. In this embodiment, IAD 1610 containselectro-optical material that flows under control of a pump, convectionforces, or other mechanisms; wherein the fluid can flow out of IAD 1610to be cooled and can flow back into IAD 1610 when cooled for control ofillumination 1611.

A preferred embodiment 1600 of an integral batch-fabricated displayarrangement of the present invention is shown in FIG. 16F. Arrangement1600 provides a batch-fabricated configuration having integral and/orimplicit structural and cooling capability in a simple, effective, andinexpensive arrangement.

In FIG. 16F, incident illumination 1611 is generated with source 1634.Source 1634 can include devices that are well known in the art such asbulbs, reflectors, lenses, etc as with prior art slide projector andmovie projector arrangements and as discussed with reference to FIG. 14.Source illumination 1611A is processed with heat filter 1636 forenhancing the visiblity-to-heat ratio (VHR) of illumination 1611. Filter1636 may be a well-known heat filter such as for filtering out infraredenergy. Filter 1636 can be mounted on structure 1637 for conductingabsorbed heat energy from filter 1636 to case 1632. Filteredillumination 1611B is incident upon IAD 1610, generating reflectedillumination 1613. IAD 1610 can be operated in a reflective mode,generating reflected illumination 1613. IAD 1610 can be attached to case1632 such as with bonding material 1630 which can be a good heatconductive material. Various attachment methods are discussed hereinand/or are well known in the art.

LCD 1610 can be bonded to heat sink 1632 with a thin thermallyconductive bonding material 1630, where heat sink 1632 can be a part ofthe enclosure of an illumination display device. Case 1632 can provide aheat sink for conducting heat energy from illumination amplifier 1610;for dispersing heat energy throughout the case; and for radiant,convective, and conductive cooling to the outside environment, asillustrated with arrows 1615-1617. Further, fins or other het sinking1633 and heat transfer devices can be provided on case 1632 to enhanceheat transfer. This can be considered to be a batch-fabricated case,mounting structure, and heat transfer media to facilitate protection,mounting, and cooling respectively of illumination amplifier 1610.

Reflected controlled illumination 1613A can be processed with projectionoptics 1638 to generate projection illuminaton 1613B for projection ontoscreen 1635 as discussed with reference to FIG. 14 herein. Projectionoptics can include lenses, prisms, and other arrangements and can havefocusing, zooming, and other capabilities well known in the projectionoptics art; as further discussed with reference to FIG. 14 herein. Case1632 can provide heat sink capability such as for dissipating heatthrough radiation 1615, convection 1616, and conduction 1617. Finnedheat sink 1633 can be used to enhance heat transfer such as withconvection heat transfer 1616.

The projection IAD arrangement shown in FIG. 16F can be used inmultitudes of different types of systems. In one embodiment, system 1600can be used as a toy or a game for providing a large screen display. Inanother embodiment, system 1600 can be used as an advertising displaysuch as an illuminated display in a store. In yet another embodiment,system 1600 can be used as a large screen information display such as toreplace well-known clock displays, temperature displays, propogatinginformation displays, scoreboard displays, billboard displays, etc. Inyet another embodiment, system 1600 can be used as a portable televisiondisplay or other pictorial display such as discussed with reference toFIG. 14 herein. In yet still another embodiment, system 1600 can be usedas a light organ display such as for projecting colored illumination inresponse to audio signals. In yet still another embodiment, system 1600can be used as a display for interactive operator communication with acomputer. And in another embodiment, system 1600 can be used as anequipment display such as in numerical control systems; machine systems;vehicular systems including sea, ground, air and space vehicles; andmany other equipment systems.

System 1600 is shown implemented with a passive cooling arrangement(FIG. 16F) that does not dissipate electrical energy for cooling such aswith conductive and free air convective cooling. This arrangement isparticularly advantageous, wherein a low power arrangement can beprovided because of the low power requirements of IAD 1610, and the lowpower (or no power) cooling requirements.

Further, the arrangement shown in FIG. 16F can be a miniaturearrangement, wherein screen 1635 can be an external screen such as awell-known detached movie projector screen, a wall, etc and thereforearrangement 1600 excluding screen 1635 can be implemented in miniatureform. In order to preserve the miniature form and low powercharacteristics, it is desirable to minimize active (power dissipating)heat transfer devices such as fans, refrigeration, thermoelectriccoolers, etc. In an alternate embodiment not having constraints such aspower, size, etc; system 1600 can be implemented with active coolingarrangements such as forced air cooling, fluid cooling, thermoelectriccooling, etc to enhance thermal considerations. Although coolingsimplicity is important for many applications, other applications mayrequire high intensity and/or large size projected images; wherein highintensity and large size require high intensity illumination from source1634. In such applications, exotic cooling techniques may be permissablein order to achieve the high intensity and/or large size projected imageon screen 1635. Such exotic techniques may include circulating theelectro-optical filler material 1659 (FIG. 16G) for coolant with anexternal refrigeration coolant device, implementing the IAD substratesto include coolant coils contained therein, implementing the internalIAD space to include coolant coils circulated therein, implementing theIAD with a heat pipe, etc.

Heat pipe technology may be used for IAD heat transfer. Such a heat pipeis characterized by the RCA Corp heat pipe product discussed in the Oct.27, 1977 issue of Electronics Magazine at page 50 therein.

A heat shield or filter can be used to further reduce heating effects.Illumination in the higher frequency or blue and violet spectral regionis more effective for displays and reduces heating compared withillumination in the red and orange spectral region, wherein this red andorange spectral region is only moderately effective for displays andproduces more pronounced heating effects. Therefore, in embodimentswhere heating effects are important, higher frequency visibleillumination such as in the blue and violet regions having a highervisibility-to-heat ratio (VHR) is more desirable than lower frequencyvisible illumination such as in the red and orange regions having alower VHR. A method for spectral selection can be implemented in variousways such as by selecting illumination sources that generateillumination towards the higher VHR spectral region; using filters thatremove illumination having a lower VHR such as heat filters, infraredfilters, and red filters; and other methods and arrangements forreducing portions of the spectrum having a lower VHR and enhancingspectral regions having a greater VHR.

In one such embodiment, source 1634 includes a source for generatingillumination having a higher VHR such as a mercury vapor lamp, afluorescent lamp, a xenon lamp, etc as preferred to lower VHR lamps suchas incandescent lamps; although such lower VHR lamps are not precludedin alternate embodiments.

In another such embodiment, heat filter 1636 removes lower VHR spectralenergy from input illumination 1611A and transmits more of the higherVHR spectral energy as filtered illumination 1611B. Heat filter 1636 canbe used and can be any known filter such as an infrared filter forreducing infrared energy which has a low VHR. Filter 1636 can remove ahigher percentage of red and orange spectral energy having a relativelylow VHR and can pass a higher percentage of blue spectral energy assignal 1611B having a higher VHR. Heat filter 1636 can absorb largeamounts of illumination energy from input illumination signal 1611A forconversion to heat energy, wherein filter 1636 can be mounted on a heatsink 1637 to conduct heat energy to case 1632 or can dissipate heatenergy in other forms such as with radiant, convective, and conductivecooling as discussed with reference to FIGS. 16A-16E herein.

Alternately, heat filter 1636 can be operated in a reflective moderather than a transmissive mode, wherein filter 1636 can transmitsand/or absorb layer VHR illumination and can reflect higher VHRillumination such as by transmitting and/or absorbing infrared and redspectral region illumination and by reflecting blue and violet spectralregion illumination. In this embodiment, the heat transfer advantagesassociated with reflective mode LCD 1610 also pertain to a reflectivemode filter. Further, transmitted filter illumination can be transmittedto a heat absorbing medium or can be transmitted to the externalenvironment to reduce heating effects. Alternately, filter 1636 cantransmit higher VHR illumination to LCD 1610 and can reflect lower VHRillumination to a heat absorbing medium or to the external environment.

In a preferred embodiment, heat transfer arrangements are discussed withreference to IAD 1610. Other devices such as source optics 1634, filter1636, projection optics 1638, etc may experience heating effects and mayrequire cooling, wherein the cooling arrangements discussed for LCD 1610are equally applicable to the other elements in the system and whereinthese cooling arrangements may be used in any combination with theelements shown in FIG. 16F. For example, source optics 1634 may becooled with forced air 1619 from blower 1618 (FIGS. 16A and 16E), filter1636 may be cooled conductively with conductive mounting 1637 (FIG.16F), illumination amplifier 1610 may be cooled with heat sink 1633(FIG. 16F), projection optics 1638 may be cooled with a freonrefrigerator, and screen 1635 may not be cooled explicitly but may becooled implicity with free air convective cooling; or alternately, manyother combinations and permutations of heat transfer arrangements may beprovided.

In a preferred embodiment of a bonded IAD arrangement, the bondingmaterial is a good heat conductor and is relatively thin to optimizeheat transfer. In prior art arrangements, the mounting device isrelatively thick and does not provide good heat transfer. For example,prior art systems use non-conductive epoxy in a relativey thick form.Also, prior art systems such as LCD electronic watches use a pressurecontact called a "zebra strip" for contacting the electrode points withelectrically conductives bumps, but providing poor thermal conductivitydue to the limited contact area, poor thermal conductivity, etc andbeing relatively thick. Therefore, it is apparent that the prior art isunconcerned with heat transfer considerations.

Although the arrangement shown in FIG. 16 has been discussed in theembodiment of an arrangement for cooling an IAD, these arrangements canalso be used for heating an IAD such as for operation at lowtemperatures. For example, heat conducting devices 1621-1624 canalternately be heating devices for conducting heat to IAD 1610. Further,fluid flow 1625 (FIGS. 16B-16D) and fluid conductor 1628 (FIG. 16E) canbe used for heating IAD 1610. Alternately, electrodes such as forexciting liquid crystal material can be resistive electrodes which maybe transparent or non-transparent for heating liquid crystal materialfor operation at low temperature conditions. Heating arrangements asdescribed herein may be thermostatically controlled such as withelectronic controls to heat liquid crystal material to maintain atemperature above the low temperature operating threshold.

Thermal considerations can be further enhanced by proper construction ofan IAD element, wherein a preferred embodiment thereof will now bediscussed with reference to FIG. 16G. The arrangement shown in FIG. 16Gis discussed in greater detail herein under the title LARGE PANELCONSTRUCTION. Illumination 1611 is shown incident on IAD 1641 operatingin a reflective mode. Reflected illumination 1613 is generated undercontrol of IAD 1641 such as by having a reflective surface at the lowersurface 1655 or at the outer surface 1645. Base 1655 provides formounting, cooling, and/or providing a reflective surface.

Heat transfer can be improved by having heat conducting materials suchas upper substrate 1644, lower substrate 1645, and filler material 1659.Upper substrate 1644 and lower substrate 1645 can be constructed of heatconductive material such as glass, plastic, and other materials that arefabricated in a form to provide good heat conduction. Such substratematerials are transparent materials in a preferred embodiment, but maybe other than transparent materials. For example, operating in areflective mode, electro-optical device 1641 can have a reflectivecoating on the inside of substrate 1645 such as at inside surface 1653,wherein transparency of lower substrate 1645 may not be an importantconsideration. Therefore, bottom substrate 1645 can be a non-transparentheat conductive substrate such as a metal substrate or other substratehaving good heat transfer characteristics.

Further, IAD 1641 can have a plurality of heat transfer devices such asdiscussed with reference to FIGS. 16A-16E, used in combination with thepreferred embodiment of a reflective mode IAD having a good heattransfer backing 1655. For example, IAD 1641 can have a picture frametype heat transfer structure on top electrode 1644 such as structure1622 (FIG. 16B), can have fluid flow cooling such as illustrated witharrow 1625 (FIGS. 16A-16D) and with arrows 1627 and 1629 (FIG. 16E), etcin combination with heat filter 1636 and heat conductive mounting of IAD1610 (FIG. 16F) and other arrangements described herein in variouscombinations. Further, IAD 1641 can have a heat conductive fillermaterial 1659 to enhance heat transfer such as using a filler materialthat has an inherently good heat conductive characteristic and/or byincluding material in filler 1659 to enhance the heat conductivitycharacteristic.

Yet further, filler material 1659 can be circulated either internal toIAD 1641 or external to IAD 1641. Internal circulation can be providedwith an internally mounted agitator, pump element, etc; by includingmagnetic particles with the filler material and inducing a magneticfield to cause fluid flow; by implementing fluid flow caused bydifferences in temperature such as used in self-cooling oil-filledelectrical transformers; and other methods that will now become obviousfrom the teachings herein. External heat transfer can be provided incombination with the above methods and arrangements or independentthereof. Pipe 1656A can introduce cooled fluids 1627 into IAD 1641 andpipe 1656B can extract heated fluids 1629 from IAD 1641. An externalpump, convective cooler, or other arrangement can be used to inducefluid flow 1627 and 1629 for cooling. The pipe comprising input segment1656A and output segment 1656B can be routed to a heat exchanger such asa heat sink 1633 (FIG. 16E) for heat transfer to the air, or to acoolant heat exchanger, or to other heat transfer devices.

The structure of substrates 1644 and 1645 (FIG. 16G) can be constructedin a manner that improves heat transfer. For example, top substrate 1644can be a thin substrate having a thin dimension 1657 to minimizeillumination absorbtion and to minimize related heating effects. Bottomsubstrate 1645 can be thicker than top substrate 1644 because bottomsubstrate 1645 is closer to heat sink 1655 and therefore provides betterheat transfer. Further, inner surface 1653 of bottom substrate 1645 canhave a reflective coating, thereby significantly reducing illuminationtransmission through bottom substrate 1645 and the related heatingeffects.

Where illumination absorbtion of filler material 1659 is an importantconsideration, it may be desirable to maximize heat transfer betweenfiller material 1659 and heat sink 1655. Therefore, lower substrate 1645may be thinner than upper substrate 1644 to enhance heat transfer fromfiller material 1659 to heat sink 1655. In yet another embodiment, uppersubstrate 1644 may have a thickness equal to or substantially the samethickness as lower substrate 1645 such as to combine the advantages of athinner upper substrate 1644 and a thinner lower substrate 1645.Therefore, heat transfer can be enhanced having a thinner lowersubstrate 1645, or a thinner upper substrate 1644, or equally thinsubstrates 1645 and 1644. Thinness is herein intended to mean thedimension transmitting illumination and/or the substrate dimension shownas cross-hatched upper dimension 1657 and lower dimension 1658.

Further cooling advantages can be achieved with evaporation, whereinevaporative cooling is highly efficient. For example, fluid can becontrolled to flow over or be sprayed over heat sink 1633 in a mannerthat causes evaporation such as is well known in the art for evaporativecooling. Similarly, fluid can be caused to flow over or be sprayed overthe surface of LCD 1610 to cool the surface having incident illumination1611, such as top surface 1644 of illumination amplifier 1641 (FIG.16G). In one embodiment, a fine mist can be sprayed over top surface1644, wherein the fineness and amounts of the spray may be such thatillumination degradation is minimal and cooling such as throughevaporation and mist effects is enhanced.

Still further, a plurality of liquid crystal elements 1610 can besequentially rotated into position such as on a rotating disk orcylinder so that each element is illuminated in sequence to provide thedesired projected image. The percentage of the energy absorbed by eachelement is related to the number of elements and therefore the heatingof any element can be significantly reduced. Such an arrangement isexemplified with a moving picture projector, where a plurality of framesof the film are rotated into the illumination beam. As the IAD isrotated out of the illumination beam, it can be cooled such as with thevarious methods discussed above. Therefore, when the IAD is rotated backinto the illumination beam, it has been sufficiently cooled to reducethermal degradation effects. More latitude is permitted in cooling ofIADs that are not in the illumination beam because there is reducedconcern for degradation of the projected image until the IAD is rotatedback into the illumination beam. For example, IADs rotated out of theillumination beam can be sprayed with a mist for cooling, passed througha wiper assembly to remove unevaporated mist, and then rotated back intothe illumination beam. Similarly, IADs rotated out of the illuminationbeam can be rotated through a water bath or other coolant, passedthrough a drying assembly, and then rotated back into the illuminationbeam.

Cooling is particularly enhanced with high velocity flow, withevaporation, and by covering a large area. For example, forced air 1619from blower 1618 and fluid 1627 and 1629 flowing in pipe 1628 (FIG. 16E)may have high velocity flow and may cool a large area. Heat sink 1633may cover a larger area than illumination amplifier 1610 for moreefficient heat transfer to the air 1616 (FIG. 16F) and air 1616 (FIG.16F) may be high velocity air 1619 generated with a high velocity blowersuch as blower 1618 (FIGS. 16A and 16E).

Still further cooling advantages can be achieved with fluid circulation.For example, prior art arrangements have been configured forrecirculating the illumination control fluid to reduce or avoidagglomeration of the particles (U.S. Pat. No. 3,788,729) but not toprovide cooling. In such prior art arrangements, heat is applied to thefluid to provide convective flow, thereby specifically precluding theobjective of the present invention for providing cooling. Nevertheless,such prior art arrangements may be used for cooling in accordance withthe arrangement of the present invention such as by convective flow,pumped flow, etc and having external heat transfer means to remove heatfrom the circulating fluid.

Yet further, closed system heat exchangers are well known and can beused with the system of the present invention. Such devices areexemplified by an automotive transmission fluid cooling system having aheat transfer arrangement in conjunction with a radiator. Transmissionfluid is circulated through a closed cooling system to preventcontamination and to provide cooling of the transmission fluid. Thetransmission fluid is circulated through a heat exchanger such as heatexchanger 1633 (FIG. 16E) and is cooled by convective air flow from theradiator and by forced air flow generated with the automobile fan suchas illustrated with blower 1618. In some applications, transmissionfluid can be circulated through the cooling water in the automotiveradiator, wherein the integrity of the transmission fluid cooling systemis preserved by conducting the transmission fluid through a sealed pipesuch as pipe 1628 (FIG. 16E).

Yet further, an illumination amplifier substrate can provide coolingsuch as with deposited metalic thermal conductors either using theconventional metallic deposited electrodes or using supplementarythermal conductors deposited or otherwise formed on substrates ofamplifier 1641. Similarly, other cooling methods may be provided as anintegral part of IAD 1641 such as coolant tubes 1628 formed in thesubstrate 1643 of amplifier 1641 for circulating cooling fluid to removeheat.

It is herein intended that the heat transfer considerations describedfor the preferred embodiment of a projection LCD arrangement also beusable with the other embodiments disclosed herein. For example, an IADwindow may be subjected to heat and cold environmental conditions,wherein the heat transfer embodiments disclosed herein may be used forheating a cold IAD window and/or cooling a hot IAD window.

Although high intensity and large size terminology pertaining todisplays are relative terms, they are self-explanatory and docharacterize the projection IAD arrangement of the present invention.

Although terminology such as high intensity illumination is notquantitative, it is illustrative in accordance with the improvement ofthe present invention. For example, prior art liquid crystal displaysuse ambient light such as room lighting in a home, which is consideredto be low intensity illumination. Further, prior art liquid crystalwatches use a very small light bulb for nighttime viewing, which is alsoconsidered to be low intensity illumination. Yet further, prior artliquid crystal displays use sunlight but are viewed in indirect ratherthan direct sunlight, which is considered to be low intensity (andnatural) illumination. Use of a high intensity source (not naturalillumination) in combination with a projection display arrangementcharacterized one feature of the present invention.

In alternate embodiments, a high intensity IAD display may becharacterized as a display that is illuminated with illumination from asource that is greater than ambient illumination; or an IAD display thatis illuminated with illumination from a source that is greater thansunlight illumination; or an IAD display that is illuminated to providegreater than ambient display illumination; or an IAD display that isilluminated with illumination from a source that is at least a one-wattsource, or is at least a four-watt source, or is at least a ten-wattsource, or is at least a 100-watt source. Further, high intensity may becharacterized as source illumination intensity that is greater thanneeded for direct viewing, wherein source illumination intensity neededfor viewing a magnified projected image is greater than needed fordirect viewing of an IAD because of the intensity reduction caused byprojection and magnification.

In alternate embodiments, size-related projection terminology may becharacterized with the table entitled SIZE RELATED ALTERNATEEMBODIMENTS; where the first column identifies an IAD dimension, thesecond column identifies a projected display dimension which maycorrespond to the related IAD dimension in the first column, and thethird column identifies the projection magnification related to suchcorrespondence. In order to broaden the example, the IAD dimensions insaid first column are defined as "less than" dimensions, while theprojected dimensions and projection magnification in said second andthird columns are defined as "greater than" dimensions.

    ______________________________________    TABLE OF    SIZE-RELATED ALTERNATE EMBODIMENTS    IAD        PROJECTED     PROJECTION    DIMENSION  DIMENSION     MAGNIFICATION    (less than)               (greater than)                             (greater than)    ______________________________________    <0.01      >0.01         >1    <0.1       >0.1          >1    <0.5       >0.5          >1    <1.0       >1.0          >1    <5.0       >5.0          >1    <10.0      >10.0         >1    <0.01      >0.1          >10    <0.1       >1.0          >10    <1.0       >10.0         >10    <10.0      >100.0        >10    <0.01      >1.0          >100    <0.1       >10.0         >100    <1.0       >100          >100    <10.0      >1,000        >100    <0.01      >10.0         >1,000    <0.1       >100          >1,000    <1.0       >1,000        >1,000    <10.0      >10,000       >1,000    <0.01      >100          >10,000    <0.1       >1,000        >10,000    <1.0       >10,000       >10,000    <10.0      >100,000      > 10,000    ______________________________________

Large Panel Construction

Large panels of electro-optical devices may be required such as forwindows and large displays. For example, large panels can be implementedwith liquid crystal material sandwiched inbetween glass substrateshaving deposited electrodes on the inner surfaces. Liquid crystalsupport is usually provided by contacts between the two glass substratesat the outer edges or periphery of a panel. For small panels, this edgesupport has been adequate. For large panels such as in accordance withthe window and display embodiments of the present invention and formultitudes of other embodiments, it may be desirable to provide supportswithin the panel interior between the outer edges. Therefore, inaccordance with another feature of the present invention, a panelarrangement is provided for construction of large panels such as withinternal support elements.

The broad teachings of the present invention for constructing largephoto-optical panels can be accomplished with many arrangements, some ofwhich are discussed above. The teachings herein are very broad and arenot limited to merely internal support structures, but include anygeneralized arrangement for implementing large panels.

A large panel element will now be discussed with reference to FIG. 16Gin the embodiment of a large LCD panel. Panel 1641 is shown insimplified form for purposes of illustration of the improvementsprovided herein, wherein construction of small panels is well known inthe art and provides a basis for this discussion on large panels. Forexample, substrate materials 1643 are shown in rectangular form having across-hatched section taken in the plane of the figure and havingexaggerated spacing between the substrate for purposes of illustration.Panel 1641 can be implemented with electro-optical materials such asliquid crystal material filling space between sandwiched substrates 1643which may be glass, plastic, or other substrates. Substrates 1643comprise upper substrate 1644 and lower substrate 1645 bonded togetherat edge 1646. In the usual prior art configuration, substrates 1644 and1645 are connected at the outer edges such as with support 1647 at theleft side and support 1648 at the right side. Electrodes are providedsuch as on the inner surface 1652 of top substrate 1644 and the innersurface 1653 of bottom substrate 1645.

In accordance with one feature of the present invention, internalsupports 1649-1651 are provided for supporting substrates 1644 and 1645inbetween edge supports 1647 and 1648. Supports 1649 and 1650 are shownat the sectioned plane of the figure and support 1651 is shown set backfrom the plane of the figure. Supports 1649-1651 are shown in simplifiedform for convenience of illustration, wherein supports 1649-1651 may besmall dimension or point supports such as support 1649, long ridge-typeor barrier-type supports such as supports 1650 and 1651, or other typesof supports for supporting substrates 1644 and 1645 inbetween outer edgeperipheral supports 1647 and 1648.

Supports or spacers can be constructed as part of substrates 1644 and1645 or can be attached to substrates 1644 and 1645 such as with bondingmethods. For example, integral construction of supports as part of thesubstrates can be provided by well-known moulding, etching, grinding,milling, etc of substrates 1644 and 1645 to provide internal orintermediate supports or spacers 1649-1651. Alternately, substrates 1644and 1645 can be constructed without internal supports, wherein internalsupports can be attached during the bonding together of substrates 1644and 1645. Alternately, supports such as supports 1649-1651 can be aninserted structure rather than a bonded structure. For example, suchsupports may be a thin honycomb structure inserted between substrates1644 and 1645 and either maintained in placed by close proximity of thesubstrates or glued or otherwise bonded to the substrates to providesupport and maintain separation between the substrates. Such a supportstructure is similar to the honeycomb structure for supporting andseparating sheets or aircraft and missile surface "skin"; as is wellknown in the airframe structural art. Internal supports 1649-1651 can bea self-supporting internal structure such as a honeycomb or otherstructure inserted between substrates 1644 and 1645 and either bonded ornot bonded thereto for providing the desired support. Many othertechniques will now become obvious to those skilled in the art from theteachings herein.

For a honeycomb-type structure or other such internal supportingstructure, the supports may be a barrier to the free flow ofelectro-optical material. This can be either desirable or undesirable,depending on the implementation. Where undesirable and where free flowof material is desired, ports or holes can be provided such as hole 1660to permit flow of the material through supporting structure 1650.

Still further, many other techniques for providing support andmaintaining separation for substrates 1644 and 1645 and many otherarrangements for implementing large photo-optical panels will now becomeobvious to those skilled in the art from the teachings herein.

The embodiment shown in FIG. 16 clearly finds antecendent basis inparent U.S. Pat. No. 3,986,022; wherein projection optics are disclosedtherein, reflective mode illumination amplifier operation is disclosedtherein, and a large screen audience display is disclosed therein andwherein the combination of these disclosures is disclosed explicitlytherein and/or is implicit therein based upon the statements ofintention of combinations of separate disclosures such as at column 56lines 14-25 therein. For example, antecedent basis for the projectiondisclosure is discussed in the next section herein.

Antecedent Basis For Projection Disclosure

The projection illumination amplifier disclosure of the presentinvention finds extensive antecedent basis in parent application Ser.No. 366,714 now U.S. Pat. No. 3,986,022. This antecedent basis will nowbe discussed to illustrate the relationship between the disclosure ofthe instant application and the disclosure of said parent application.

In said parent application, illumination amplifiers have been discussedfor applications wherein projection is implicit therein. For example,use of an illumination amplifier in the disclosed camera system andphotoplotter system establishes the projection nature of theillumination amplifier arrangement. Further, use of an illuminationamplifier in combination with lenses further establishes the projectionnature of the illumination amplifier arrangement. A detailed discussionof specific disclosures in said parent application providing antecedentbasis with references to U.S. Pat. No. 3,986,022 is provided below.

Control of projected illumination with an illumination amplifier findsantecedent basis in U.S. Pat. No. 3,986,022; particularly with referenceto the photographic camera embodiments therein and implicit in thearrangements having lens arrangements therein. Camera systems areillustrated in FIGS. 8-10 therein and various lens arrangements areillustrated in FIGS. 6D, 9A, 9C, and 10 therein. Further, camera systemsare discussed at column 41 line 46 to column 48 line 37 therein and lensarrangements are discussed at column 13 lines 33-49, column 31 lines 1-7and lines 31-33, column 42 lines 35-39, column 45 line 61 to column 46line 6, column 57 lines 19-37, and elsewhere therein.

The projection arrangement of the present invention is further shown inthe discussions of FIGS. 8A-8C at column 42 line 1 to column 45 line 29therein; wherein shutter and aperture arrangements and rotationarrangements 800, 820, and 820C (FIGS. 8A, 8B, and 8C respectively) aredisclosed in the preferred embodiment of a photoplotter system such asthe photoplotter system referenced and incorporated by reference fromU.S. Pat. No. 3,738,242 (U.S. Pat. No. 3,986,022 at column 1 lines 14-18and lines 40-44; column 42 at lines 15-19; column 43 at lines 16-25 andelsewhere therein). Said U.S. Pat. No. 3,738,242 sets forth aprojection-type illumination control system having illumination source48; projection objects 68, 70, and 71; shutter 69; aperture 73; androtation device 10. Substitution of the illumination amplifier aperture,shutter, and rotation devices of the present invention (as discussedrelative to FIGS. 8A-8C in said U.S. Pat. No. 3,986,022) provides forillumination amplifier control and in particular liquid crystal controlof projection illumination with the rotation control, aperture, and/orshutter of said U.S. Pat. No. 3,986,022. Further, terminology oftransmitted illumination in said U.S. Pat. No. 3,986,022 such as atcolumn 31 lines 41-43, column 46 lines 2-6, and elsewhere thereincorresponds to the term projected illumination of the instantapplication.

Further, the use of coherent illumination such as from a laser source isdisclosed in U.S. Pat. No. 3,986,022 at column 57 lines 4-9 for thevarious embodiments set forth therein and therefore can be used invarious combination with the projection arrangement, as discussedherein.

Further, an audience display system is disclosed in U.S. Pat. No.3,986,022 at FIG. 11 and at column 52 line 1 to column 55 line 27therein, wherein it was stated therein as being intended that thevarious features in the disclosure that are set forth individually becombinable in various combinations such as at column 56 lines 14-47,column 57 lines 19-31, and elsewhere therein.

The projection feature of the photo-optical arrangement of said U.S.Pat. No. 3,738,242 is clearly established at column 1 lines 48-52therein which states " . . . an optical arrangement required to projectthe image of the aperture onto the film . . . " [emphasis added];clearly combining the aperture therein in a projection arrangement andwherein said aperture in the preferred embodiment of U.S. Pat. No.3,986,022 is an illumination amplifier aperture in accordance with theprojection illumination amplifier arrangement of the present invention.

In view of the above, the projection illumination amplifier arrangementand the laser coherent light source features of the present inventionfind ample antecedent basis in parent U.S. Pat. No. 3,986,022.

Pulse Modulated Control

Pulse modulated control can be implemented with the system of thepresent invention for various uses exemplified by machine control andillumination control; as discussed in the referenced patentapplications, as is well known in the art, and as further discussedherein. Although pulse modulation may herein be exemplified withpulsed-width-modulation, it is herein intended thatpulse-width-modulation be exemplary of other types of pulse modulationsuch as pulse-rate-modulation, pulse-code-modulation, and other types ofpulse modulation.

A pulse modulation arrangement for use with a sound system such as ahigh fidelity and/or stereo type sound system will now be discussed withreference to FIG. 1A of U.S. Pat. No. 4,016,540. Data processor 112 cangenerate control signals which as whole number and discrete controlsignals 123 and 126 to interface electronics such as elements 120-122and to device 124 which can be a pulse-width-modulated sound system. Forexample, machine 124 can be a sound transducer such as a speaker andelectronic devices 120-122 can be pulse-width-modulated amplifier andcontrols used in place of the pulse-width-modulated servos which arediscussed in the referenced patent applications. Alternately, pulsemodulated digital signals can be generated with data processor 112 suchas with a discrete output signal which can be signal 101 to interfacedevice 100. In an embodiment where signal 101 is a pulse modulatedsignal, element 102 can be a power amplifier to generate pulse modulatedsignal 103 as a power signal to drive transducer 104 to generate soundsignal 105. Use of a data processor to generate a pulse modulated outputsignal such as with a discrete signal is discussed in referencedapplication Ser. No. 134,958 at page 22 line 2 to page 23 line 15 andelsewhere in the referenced patent applications. The above-describedarrangement can be used for a sound response system such as discussedwith reference to interface 100 (FIG. 1A) which may be used for a toy, agame, or multitudes of other uses some of which are discussed inreferenced U.S. Pat. No. 4,016,540. Further uses of this pulsemodulation arrangement will now become obvious from the teachingsherein.

Pulse-width-modulation has been discussed in detail in the referencedpatent applications for a machine control embodiment and for anillumination control embodiment, wherein these disclosures have beenincorporated herein by reference. For example, a pulse-width-modulationarrangement is been disclosed in referenced application Ser. No. 101,881particularly with reference to FIGS. 1 and 16-19 therein; at page 33lines 13-27, page 85 lines 23-25, page 86 lines 7-24, and page 88 lines11-15; and elsewhere therein. Further, a pulse-width-modulationarrangement has been disclosed in referenced application Ser. No.134,958 particularly at page 3 lines 21-28, page 6 lines 14-24, and page22 line 2 to page 23 line 15, and elsewhere therein. Yet further, apulse-width-modulated arrangement has been disclosed in referencedapplication Ser. No. 135,040 particularly at page 10 lines 10-15, page18 lines 16-26, page 22 lines 1-28, page 24 lines 14-28, page 26 lines10-16, page 31 line 4 to page 32 line 5, and elsewhere therein. Stillfurther, a pulse-width-modulation arrangement has been disclosed inreferenced application Ser. No. 246,867 particularly in FIGS. 4A and 4B;at page 24 lines 27-33 and page 27 line 1 to page 34 line 30; andelsewhere therein. Yet further, a pulse-width-modulated arrangement hasbeen disclosed in referenced application Ser. No. 302,771 particularlywith reference to FIGS. 5, 6, and 8; at page 21 line 30 to page 22 line2 and page 57 line 1 to page 67 line 24; and elsewhere therein. Stillfurther, a pulse-width-modulated arrangement has been disclosed inreferenced applications Ser. No. 366,714; Ser. No. 727,330; and Ser. No.730,756 particularly with reference to FIGS. 2 and 6E and at page 16lines 10-19, page 17 line 1 to page 21 line 15, page 46 lines 18-30, andpage 48 lines 12-34; and elsewhere therein and further with reference toapplications Ser. No. 727,330 and Ser. No. 730,756 particularly at page172 lines 9-25 and elsewhere therein.

As an alternate embodiment to the D/A converter of the interface device,a pulse modulated or other duty cycle modulated arrangement can be used.Such a duty cycle arrangement provides particular advantages, where aduty cycle device may be a digital device which may be more compatiblewith the digital electronics of the digital audionic system than wouldbe a hybrid D/A converter arrangement. Various pulse modulated devicessuch as pulse-width-modulated devices are set forth in the copendingapplications in the chain of related applications which are incorporatedby reference such as for the pulse-width-modulated servo drives ofreferenced applications Ser. No. 101,881; Ser. No. 134,958; Ser. No.135,040; Ser. No. 339,817 now U.S. Pat. No. 4,034,276; and Ser. No.339,688 and for illumination control in referenced applications Ser. No.366,714 now U.S. Pat. No. 3,986,022; Ser. No. 727,330; and Ser. No.730,756 set forth a pulse-width-modulated arrangement in FIGS. 2B, 2C,and 2D therein. Further, various pulse-width-modulated drives arecommercially available and may be used with the system of the presentinvention for output transducer drivers in place of the D/A converterarrangement discussed herein.

In one embodiment such as discussed herein with reference to FIG. 17, apulse-width-modulated signal may be generated with a counter such as byloading the output digital number into the counter and permitting thecounter to count-down to zero. When the counter counts-down to zero,detection of the counter zero condition or the counter overflowcondition can be used to reset a flip-flop. The flip-flop can be set atthe start of the new cycle. Therefore, the output of the flip-flop setat the beginning of a cycle and reset after a controlled period of timeprovides a pulse-width-modulated output signal to driven an outputtransducer. Alternately, the pulse-width-modulated signal can begenerated under program control of the computer, where the computer canset the flip-flop at the beginning of a cycle and can provide a programtime delay for resetting the flip-flop thereby performing the samefunction as the counter described above; such as discussed in greaterdetail in the related applications referenced herein.

Further, the pulse modulated servo arrangement of the referenced patentapplications set forth interface register and counter arrangements forinterfacing a computer to a servo. These arrangements are exemplary ofinterfacing a computer to a sound generation arrangement wherein servoelectronics 120-122 of the referenced patent applications is exemplaryof sound interface electronics and wherein machine 124 of the referencedpatent applications is exemplary of a sound transducer such as aspeaker.

The audionic system of U.S. Pat. No. 4,016,540 has been discussed in apreferred embodiment using a digital-to-analog converter 102 tointerface between data processor 112 and transducer 104 (FIG. 1A).Alternately, other arrangements can be used including analog, hybrid,and digital arrangements as disclosed in U.S. Pat. No. 4,016,540particularly at column 7 lines 15-24 and also at column 5 line 67 tocolumn 6 line 19 and elsewhere therein. An analog embodiment isexemplified by the direct outputting of analog signals stored in ananalog ROM or other analog memory as discussed in referenced applicationSer. No. 812,285 such as at page 41 line 16 to page 42 line 7 andelsewhere therein. A hybrid (analog and digital) embodiment ischaracterized by the digital-to-analog converter arrangement discussedin U.S. Pat. No. 4,016,540 with reference to FIG. 3. A digitalembodiment can be implemented as the pulse modulated embodimentdiscussed herein such as with reference to FIGS. 9A and 9B. Further, adigital embodiment is illustrated in the referenced applications such asapplications Ser. No. 101,881; Ser. No. 134,958; Ser. No. 135,040; Ser.No. 302,771; etc such as for controlling analog servos withpulse-width-modulated signals as discussed elsewhere herein whereindigital commands are loaded into counters and registers for controllingpulse-width-modulated servos. Many other embodiments will now becomeobvious to those skilled in the art from the teachings herein.

Time-Domain Pulse Modulation

A time-domain pulse modulator will now be discussed for a preferredembodiment using the monolithic computer of the system of the presentinvention for generating a pulse-width-modulated signal under programcontrol. Other pulse modulation arrangements will now become obviousfrom the teachings herein such as using program controlled arrangementsas described herein and as described in related application Ser. No.134,958 at page 22 line 2 to page 23 line 15; or using hardwiredarrangements as disclosed in the related patent applications referencedherein; or using other computers, programs, and/or arrangements as willnow become obvious from the teachings herein.

A program controlled pulse-width-modulation arrangement will now bediscussed with reference to FIGS. 17A and 17B. An interface arrangement971 consistent with the data processor of referenced application Ser.No. 101,881 is illustrated in FIG. 9A. A flow diagram 976 for generatinga pulse-width-modulated signal with arrangement 971 (FIG. 17A) isillustrated in FIG. 17B. Arrangement 971 constitutes set-reset flip-flop972 which is set by discrete output signal DO-8, reset by discreteoutput signal DO-9, and used to control device 974 with output signal975 from flip-flop 972. Device 974 can be an audio speaker, a servo, orother device controlled with a pulse modulated signal. Amplifier 973 canbe used to amplify output signal 975 to drive output device 974.Feedback signal DI-8 provides feedback on the state of flip-flop 972 tothe data processor. The data processor generates signal DO-8 to setflip-flop 972 and generates signal DO-9 to reset flip-flop 972 underprogram control using discrete output instructions. A time delay betweengenerating the DO-8 signal and the DO-9 signal controls the time periodthat output signal 975 is in the high state or the duty cycle of outputsignal 975. Therefore, the duty cycle of output signal 975 can bedirectly controlled by the data processor under program control. Oneform of program control which is exemplary of a wide range of methods isdiscussed herein with reference to FIG. 17B.

Flow diagram 976 (FIG. 17B) illustrates one method for generatingpulse-width-modulated signal 975 under program control. The computerenters subroutine 976 through operation 977 and exits subroutine 976through operation 983 with well-known subroutine operations. Forexample, ENTER operation 977 can include a calling sequence such assaving the return address to the main program or to the executiveprogram and EXIT operation 983 can include fetching the stored returnaddress and transferring back to the main program location defined withthe return address, as is well known in the computer programming art.

After entering subroutine 976 through operation 977, the programinitializes the subroutine such as by loading parameters or constantsinto various registers and memory locations. For example, a time delayword that defines the width of the pulse-width-modulated signal isdefined as the N_(o) parameter which is loaded into the N scratchpadregister; wherein this scratchpad register designation is provided forconvenience and may be assigned to any scratchpad register or otherstorage in the computer. The time delay number N_(o) can be provided asa stored constant, or generated under program control, or generated byvarious known methods to determine the time delay between discreteoutput signals which determines the width of output pulse 975 andtherefore the information content of the pulse-width-modulated signal.

The program generates the DO-8 signal with a discrete output instructionto set flip-flop 972 with operation 979 and then executes a time delayiterative routine using decrement operation 980 and test operation 981to control the width of pulse-width-modulated output signal 975. TheN-parameter is successively decremented in operation 980 to provide atime delay and tested with operation 981 to detect when the time delayhas expired. Operations 980 and 981 can be implemented with a decrementand transfer on non-negative instruction, where the N-parameter in theN-register is decremented and the program operation transferred untilthe N-parameter is decremented to a negative number. The conditionaltransfer on the N-parameter being non-negative is shown by the loopingback from the test operation 981 to the decrement operation 980 alongthe positive path. When the N-parameter has been decremented to anegative number, the conditional transfer is disabled and the programoperations continue in sequence to operations 982 and 983.

Operation 982 discontinues the puse-width-modulated output signal 975 bygenerating the DO-9 signal with a discrete output instruction toflip-flop 972. Program operation then continues to exit operation 983 toexit the subroutine.

SCOPE AND DEFINITIONS

The invention disclosed herein is presented in preferred embodiments ofillumination control arrangements to exemplify the inventive features,but the scope of this invention is much broader than illustrated withthese preferred embodiments. Therefore, the scope is intended to bebroadly interpreted to cover the general fields of illumination control.

Various publications may be used for providing background for thisinvention and for illustrating the prior art. The various subject areasand associated references for each subject area are listed below.

(1)Integrated circuit technology is described in the book IntegratedCircuits by Raymond M. Warner, Jr. and James N. Fordemwalt (Editors) forMcGraw-Hill Book Company (1965).

(2) Digital computer technology is described in the books

(a) Digital Computer Design by Edward L. Braun for Academic Press (1963)and

(b) Digital Computer Design Fundamentals by Yaohan Chu for McGraw Hill(1962).

(3) Digital computer programming is described in the books

(a) Programming: An Introduction to Computer Languages and Techniques byWard Douglas Maurer for Holden Day Inc. (1968),

(b) Programming for Digital Computers by Joachim Jeenel for McGraw Hill(1959), and

(c) Elements of Computer Programming by Swallow and Price for Holt,Rinehart, and Winston (1965).

(4) Analog computer technology is described in the book Methods forSolving Engineering Problems Using Analog Computers by Leon Levine forMcGraw Hill (1964).

(5) Servo technology is described in the book Automatic Control Systemsby Benjamin C. Kuo for Prentice-Hall (1962).

(6) Illumination technology is described in the books

(a) Optics, A Course For Engineers and Scientists by Charles Williamsand Orville Becklund for John Wiley and Sons Inc,

(b) Optical Data Processing by Arnold Roy Shulman for John Wiley andSons Inc, and

(c) Optics by Bruno Rossi for Addison-Wesley (1957).

(7) Integrated circuits are described in the book The TTL Data Book ForDesign Engineers from Texas Instruments Incorporated.

(8) Thermal design is described in the articles

(a) What's New in Cool(ing)? by W. S. Hudspeth in the May 1977 issue ofElectro-Optical Systems Design magazine at pages 32-37,

(b) A New Approach to High-Power Microstrip Attenuators by Jerry McNealand Larry Gordon in the October 1977 issue of Electronic Packaging andProduction magazine at pages 109 and 110, and

(c) Cold-Plate Thermal Design, Analysis and Sizing by Ira Leonard andSteven Axelband in the October 1977 issue of Electronic Packaging andProduction magazine at pages 101-107.

Various elements of the present invention have been described hereinseparately for simplicity. In a preferred embodiment, various elementsof the present invention may be used in combination to provide thecombined advantages of the individual elements. These combinations willbecome obvious to those skilled in the art from the teachings of thisinvention. As an example the combination of the aperture size device 820(FIG. 8B), aperture rotational device 800 (FIG. 8A), and shutter device838 (FIG. 8D) can be provided by combinations of the patterns describedfor each independent arrangement.

Illumination processing arrangements may be shown to illustrateindividual features and may not repeat description of other arrangementsthat are described herein or that will become obvious to those skilledin the art from the teachings of this invention. For example: aperture,shutter, and control arrangements are individually discussed in detailherein but may not be repeated for each specific description. It isintended that such aperture, shutter, and control arrangements beuseable with other arrangements described herein such as theillumination computer. In general, it is intended that all individualfeatures of this invention be useable in combination with all otherindividual features of this invention.

Inventive features that may be used in combination include open loop orclosed loop excitation, digital or analog excitation, aperture andshutter devices, and other such features. Further, such combinations maynot be individually distinguishable where, for example, the aperture andshutter devices may be integrated together by making all aperturesegments 826-830 (FIG. 8B) reflective to provide shutter capability.

For the various embodiments discussed herein, the illumination amplifiermay be an integral part of an illumination source such as a glassenclosure of a bulb, an intermediate device placed inbetween a sourceand a receiver, or other such arrangement.

Illumination is herein intended to be interpreted in broad form and isintended to mean generalized illumination including light, both visibleand non-visible, electron beams, generalized electromagnetic radiationincluding microwaves, and other forms of illumination. Illumination isintended to further include natural light from the sun, generated lightsuch as from a light bulb, coherent light such as from a laser, andnon-visible light such as infra-red and ultra-violet illumination.Illumination may herein be referred to as illumination signals andillumination beams to describe directed illumination. Illumination mayhave a broad spectrum or a narrow spectrum. Well known illuminatonprocessing devices such as filters may be used to selectively provideillumination of a desired spectral characteristic. The term illuminationas used herein may mean a particular characteristic of an illuminationsignal such as intensity, intensity of a particular spectral region, orother illumination characteristic.

An illumination source is herein intended to be interpreted in broadform and may include a single source or a plurality of sources, a lightbulb source for visible light, a laser or maser source for coherentillumination, the sun as a source of natural sunlight, and other sourcesof illumination.

A preferred embodiment of an illumination amplifier is discussed hereinas a variable transmissivity or reflectivity device such as the wellknown liquid crystal devices. Terms used herein such as illuminationcontrol device or illumination amplifier are intended to include such avariable transmissivity or reflectivity device, but is also intended toinclude other illumination control devices such as variable absorptionand variable filtering devices.

Illumination processing devices are well known to those skilled in theart. Different types of illumination may require different types ofprocessing devices. For example lenses, prisms, mirrors, filters,shutters, and apertures may be used for visible illumination; magneticand electric fields may be used for electron beams; and other well knowndevices may be used for other types of illumination. These illuminationprocessing devices perform functions such as collimating, focusing,blocking, shaping, and filtering illumination. Because theseillumination processing devices and their use are well known, suchdevices may not be described herein unless necessary to furtherillustrate operation.

Illumination may be imaged, collimated, focused or otherwise processedwith illumination processing devices. An image may be used to illuminateor to expose an illumination sensitive medium such as film for recordingthe image such as by exposing or otherwise affecting the medium.

An illumination amplifier such as a liquid crystal device that convertsbetween reflective and transmissive characteristics can be provided incomplement illumination arrangements. Complement illuminationarrangements will be illustrated with reference to FIG. 3A, where sourceillumination is directed to illumination amplifier 300 which may be aliquid crystal amplifier. The transmissive characteristic of amplifier300 permits transmitted illumination 302 to be transmitted throughamplifier 300 to illumination receiver 303. The reflectivecharacteristic of amplifier 300 permits reflected illumination 304 to bereflected from amplifier 300 to illumination receiver 305. Assumingconservation of illumination and constant input illumination 301, as thereflectivity of 300 is increased, the transmissivity is decreased, andconversely. Therefore as transmitted illumination 302 is increased,reflected illumination is decreased, and conversely. A complementarrangement can be illustrated with a simple example, where it isdesired to first fully illuminate, then to remove illumination from anillumination receiver. For this example, the receiver can be arranged asreceiver 303, where amplifier 300 can be made transmissive forilluminating receiver 303 and then be made reflective for removingillumination from receiver 303. In a complement arrangement, thereceiver can be arranged as receiver 305, where amplifier 300 can bemade reflective for illuminating receiver 305 and then can be madetransmissive for removing illumination from receiver 305. Because of thecomplementing characteristics of reflective-transmissive illuminationamplifier devices, it will now become obvious that either of thecomplement arrangements may be used for implementing an illuminationamplifier arrangement. For simplicity, only one of the complement formsis usually described herein. It is herein intended that either of thecomplement illumination amplifier forms be useable with an embodiment,even though an embodiment may only be described relative to one of suchcomplement forms.

The features of the present invention have been described for thepreferred embodiment of an IAD, but these features may be applied toother illumination systems. For example, the pulse modulationarrangement can be applied to light emitting diode (LED) displays and toplasma displays to provide shades of intensity as discussed herein forthe IAD embodiment. Further, the flat-plane IAD embodiment disclosedherein such as with reference to FIG. 6 can be used in conjunction withLED and plasma display devices.

Many features of the present invention are related to the machinecontrol parent applications referenced herein. For example, a camera maybe considered to be a machine and a photoplotter clearly bridges thetechnologies between a conventional photographic camera and a machine.Control of illumination and control of a machine, particularly with themicrocomputer of the present invention and with other controlarrangements are disclosed in detail in the chain of copendingapplications. Therefore, control of illumination and control of machinesfinds extensive basis in the instant application and in the chain ofcopending applications.

From the above description it will be apparent that there is thusprovided a device of the character described possessing the particularfeatures of advantage before enumerated as desireable, but whichobviously is susceptible to modification in its form, method,mechanization, operation, detailed construction and arrangement of partswithout departing from the principles involved or sacrificing any of itsadvantages.

While in order to comply with the statute, the invention has beendescribed in language more or less specific as to structural features,it is to be understood that the invention is not limited to the specificfeatures shown, but that the means, method, and construction hereindisclosed comprise the preferred form of several modes of putting theinvention into effect, and the invention is, therefore, claimed in anyof its forms or modifications within the legitimate and valid scope ofthe appended claims.

I claim:
 1. A scanner system comprising:an illumination source forgenerating source illumination; an electrical control device forgenerating a plurality of sequential electrical scanning signals; and aliquid crystal device for controlling the source illumination togenerate scanning illumination in response to the plurality ofsequential electrical scanning signals generated with said electricalcontrol device, said liquid crystal device including a plurality ofsegments each segment being selectable in response to a sequentialelectrical scanning signal generated with said electrical control deviceto control the source illumination, wherein said liquid crystal devicegenerates the scanning illumination under control of the sequentialelectrical scanning signals selecting each of the plurality of segmentsin sequence.
 2. The system as set forth in claim 1 above, furthercomprising conduction means for removing heat from said electro-opticaldevice.
 3. The system as set forth in claim 1 above further comprising ahigh intensity source of illumination wherein said electro-opticaldevice includes means for generating the scanning illumination inresponse to the high intensity illumination.
 4. The system as set forthin claim 3 above, further comprising projection means for projecting thescanning illumination.
 5. The system as set forth in claim 4 above,further comprising means for generating a large screen projected imagein response to the projected scanning illumination.
 6. The scannersystem as set forth in claim 1 above, wherein said illumination sourceis a high intensity illumination source for generating high intensitysource illumination, wherein said liquid crystal device includes meansfor generating the scanning illumination as high intensity coloredscanning illumination in response to the plurality of sequentialelectrical scanning signals generated with said electrical controldevice, wherein said high intensity source illumination causes heatingof said liquid crystal device, and wherein said system further comprisesheat transfer means for removing heat caused by the heating of saidliquid crystal device by said high intensity illumination.
 7. The systemas set forth in claim 1 above, wherein said illumination source includesa plurality of separate illumination sources each generating sourceillumination having a color different from the color of the sourceillumination of the other illumination sources in said plurality ofseperate illumination sources, wherein said liquid crystal deviceincludes a plurality of seperate liquid crystal devices each controllingthe source illumination generated by a different one of said pluralityof seperate illumination sources to generate scanning illuminationhaving a color different from the color of the scanning illuminationgenerated by each of the other liquid crystal devices in response to theplurality of sequential electrical scanning signals generated with saidelectrical control device.
 8. The system as set forth in claim 1 above,further comprising feedback means for generating a feedback signal inresponse to the scanning illumination generated with said liquid crystaldevice; wherein said electrical control device includes means forgenerating the plurality of sequential electrical scanning signals inresponse to the feedback signal generated with said feedback means. 9.The system as set forth in claim 1 above, further comprising feedbackmeans for generating a feedback signal in response to the sourceillumination generated with said illumination source; wherein saidelectrical control device includes means for generating the plurality ofsequential electrical scanning signals in response to the feedbacksignal generated with said feedback means.
 10. The system as set forthin claim 1 above, wherein said system is a display system for displayinginformation to a person and wherein said system further comprisesprojection means for projecting the scanning illumination generated withsaid liquid crystal device for display of the scanning illumination to aperson.
 11. The system as set forth in claim 1 above, wherein saidillumination source includes means for receiving natural illuminationand a lens for optically processing the natural illumination to generatethe source illumination.
 12. The system as set forth in claim 1 above,wherein said illumination source includes means for receiving naturalillumination and a lens for optically processing the naturalillumination to generate the source illumination.
 13. A scanner systemcomprising:an illumination source for generating high intensity sourceillumination; an electrical control device for generating sequentialelectrical scanning signals; a liquid crystal device having a pluralityof segments selectable under control of the sequential electricalscanning signals generated with said electrical control device tocontrol the high intensity source illumination for generating highintensity scanning illumination, wherein the high intensity sourceillumination causes heating of said liquid crystal device; and heattransfer means for removing heat from said liquid crystal device causedby the high intensity source illumination heating of said liquid crystaldevice.
 14. A scanner system comprising:an illumination source forgenerating source illumination; a raster electrical control device forgenerating electrical raster scanning signals; a liquid crystal devicefor generating raster scanning illumination in response to the sourceillumination generated with said illumination source under control ofthe electrical raster scanning signals generated with said rasterelectrical control device; said liquid crystal device including aplurality of segments each selectable in response to the electricalraster scanning signals to control the source illumination, wherein saidliquid crystal device includes means for generating the raster scanningillumination under control of the electrical raster scanning signalsselecting each of the plurality of segments in sequence.
 15. The systemas set forth in claim 14 above, wherein said system is a liquid crystaltelevision receiver system, wherein said raster electrical controldevice includes means for generating the electrical raster scanningsignals as television raster scanning signals, wherein said liquidcrystal device is a television receiver screen for generating the rasterscanning illumination as a television image in response to the sourceillumination generated with said illumination source under control ofthe electrical television raster scanning signals generated with saidraster electrical control device.
 16. The system as set forth in claim14 above, wherein said system is a colored television receiver system,wherein said raster electrical control device includes means forgenerating the electrical raster scanning signals as colored televisionraster scanning signals, wherein said liquid crystal device is a coloredtelevision receiver screen for generating the raster scanningillumination as a colored television image in response to the sourceillumination generated with said illumination source under control ofthe electrical television raster scanning signals generated with saidraster electrical control device.
 17. A scanner system comprising:anillumination source for generating source illumination; an electricalcontrol device for generating a plurality of electrical scanning signalsas random scanning signals; and a liquid crystal device for generatingrandom scan illumination in response to the plurality of random scanningsignals, said liquid crystal device including a plurality of segmentseach selectable in response to a random scanning signal to control thesource illumination, wherein said liquid crystal device generates thescanning illumination under control of the random scanning signalsrandomly selecting each of the plurality of segments.
 18. A scannerdisplay system for displaying an image to an operator, said scannerdisplay system comprising:a display control device for generatingelectrical scanning signals; and a liquid crystal display forcontrolling the source illumination to generate scanned displayillumination in response to the electrical scanning signals generatedwith said display control device, said liquid crystal display includinga plurality of segments each selectable in response to the electricalscanning signals to control the illumination, wherein said liquidcrystal display generates the scanning display illumination undercontrol of the electrical scanning signals selecting each of theplurality of segments in sequence.
 19. The system as set forth in claim18 above, wherein said system is a colored scanner display system,wherein said system further comprises a plurality of coloredillumination sources each generating source illumination having a colorthat is different from the color of the source illumination from each ofthe other colored illumination sources, and wherein said liquid crystaldisplay includes means for generating a colored display image bycontrolling the source illumination generated by said plurality ofcolored illumination sources in response to the electrical scanningsignals generated with said display control device.
 20. The system asset forth in claim 18 above, wherein said system further comprisesprojection means for generating a projected display in response to thescanned display illumination generated by said liquid crystal display inresponse to the electrical scanning signals generated with said displaycontrol device.
 21. The system as set forth in claim 18 above, whereinsaid system is a colored projection scanner display system, wherein saidsystem further comprises a plurality of colored illumination sourceseach generating source illumination having a color that is differentfrom the color of the source illumination from each of the other coloredillumination sources, wherein said liquid crystal display includes meansfor generating the scanned display illumination as a colored scanneddisplay illumination image by controlling the source illuminationgenerated by said plurality of colored illumination sources in responseto the electrical scanning signals generated with said display controldevice, and wherein said system further comprises projection means forgenerating a projected color display image in response to the scanneddisplay illumination generated with said liquid crystal displayillumination.
 22. A scanner system comprising:an illumination source forgenerating source illumination; an electrical control device forgenerating electrical scanning signals; and a liquid crystal device forcontrolled reflection of the source illumination to generate scanningillumination in response to the electrical scanning signals generatedwith said electrical control device.
 23. The system as set forth inclaim 22 above, wherein said liquid crystal device said liquid crystaldevice includes a plurality of segments each segment being selectable inresponse to the electrical scanning signals generated with saidelectrical control device to control the source illumination, andwherein said liquid crystal device generates the scanning illuminationunder control of the electrical scanning signals selecting each of theplurality of segments in sequence.
 24. The system as set forth in claim22 above, wherein said illumination source is a high intensityillumination source for generating high intensity source illumination,wherein said liquid crystal device includes means for controllingreflection of the high intensity source illumination to generate thescanning illumination in response to the electrical scanning signalsgenerated with said electrical control device, wherein said controlledreflection causes heating of said liquid crystal by said high intensitysource illumination, and wherein said system further comprises coolingmeans for removing heat caused by said controlled reflection of saidhigh intensity illumination from the backside of said liquid crystaldevice.
 25. The system as set forth in claim 22 above, wherein saidillumination source includes means for generating the sourceillumination as multi-colored source illumination, wherein said liquidcrystal device includes means for controlling reflection of themulti-colored source illumination to generate the scanning illuminationas multi-colored scanning illumination in response to the electricalscanning signals generated with said electrical control device.
 26. Thesystem as set forth in claim 22 above, wherein said illumination sourceincludes means for receiving natural illumination and a lens foroptically processing the natural illumination to generate the sourceillumination.
 27. A liquid crystal scanner system comprising:anelectrical control device for generating an electrical scanning signaland a liquid crystal device for generating scanning illumination bycontrolled reflection of illumination in response to the electricalscanning signal.
 28. A scanner system comprising:illumination inputmeans for generating input illumination; an electrical control devicefor generating electrical scanning signals in response to an electricalfeedback signal; a liquid crystal device for controlling the inputillumination generated with said illumination input means to generatescanning illumination in response to the electrical scanning signalsgenerated with said electrical control device; and feedback means forgenerating the electrical feedback signal to said electrical controldevice in response to the scanning illumination generated with saidliquid crystal device.
 29. The system as set forth in claim 28 above,wherein said liquid crystal device includes a plurality of segments eachsegment being selectable in response to the electrical scanning signalsgenerated with said electrical control device to control the inputillumination, wherein said liquid crystal device generates the scanningillumination under control of the electrical scanning signals selectingeach of the plurality of segments in sequence.
 30. A scanner systemcomprising:an illumination source for generating source illumination; anelectrical control device for generating pulse width modulatedelectrical scanning signals to provide illumination intensity control; aliquid crystal device for controlling intensity of the sourceillumination to generate intensity controlled scanning illumination inresponse to the pulse width modulated electrical scanning signalsgenerated with said electrical control device.
 31. A scanner systemcomprising:an illumination source for generating source illumination; anelectrical control device for generating intensity modulated electricalscanning signals to provide illumination intensity control; a liquidcrystal device for controlling intensity of the source illumination togenerate intensity controlled scanning illumination in response to theintensity modulated electrical scanning signals generated with saidelectrical control device.
 32. A scanner system comprising:anillumination source for generating source illumination; an electricalcontrol device for generating a plurality of electrical scanningsignals; and a liquid crystal device for generating scanningillumination in response to the plurality of electrical scanningsignals, said liquid crystal device including a plurality of segmentseach selectable in response to a scanning signal to control the sourceillumination, wherein said liquid crystal device generates the scanningillumination under control of the electrical scanning signals selectingeach of the plurality of segments; and feedback means for generating afeedback signal in response to the scanning illumination from saidliquid crystal device; wherein said electrical control device includesmeans for generating the electrical scanning signals in response to thefeedback signal from said feedback means.
 33. A scanner systemcomprising:an illumination source for generating source illumination; ascan control device for generating scan control signals; and a liquidcrystal device for controlling the source illumination to generatescanning illumination in response to the scan control signals generatedwith said scan control device; and projection means for generatingprojected scanning illumination in response to the scanning illuminationgenerated with said liquid crystal device.
 34. A scanning display systemfor generating colored scanning illumination, said scanning displaysystem comprising:a first color illumination source for generating firstsource illumination having a first color; a second color illuminationsource for generating second source illumination having a second colorthat is different from said first color; a display control device forgenerating sequential electrical scanning signals; a first liquidcrystal device for generating first scanned illumination having thefirst color in response to the first source illumination generated withsaid first color illumination source under control of the sequentialelectrical scanning signals generated with said display control device;a second liquid crystal device for generating second scannedillumination having the second color in response to the second sourceillumination generated with said second color illumination source undercontrol of the sequential electrical scanning signals generated withsaid display control device; and means for combining the first scannedillumination generated with said first liquid crystal device and thesecond scanned illumination generated with said second liquid crystaldevice to generate a multicolored illumination display.
 35. A scannersystem comprising:an illumination source for generating sourceillumination; a stored program computer for generating a scan controlsignal, said stored program computer including1. a main memory forstoring a program,
 2. execution means for generating the scan controlsignal under control of the program stored in said main memory, and 3.output means for outputting the scan control signal under control of theprogram stored in said main memory; and a liquid crystal device forcontrolling the source illumination to generate scanning illumination inresponse to the scan control signal output from said stored programcomputer output means.
 36. A scanning system comprising:an illuminationsource for generating source illumination; a liquid crystal device forcontrolling the source illumination to generate scanning illumination inresponse to a scan control signal output from a stored program computer;and a stored program computer for outputting the scan control signal inresponse to the scanning illumination generated with said liquid crystaldevice, said stored program computer including1. a main memory forstoring a program,
 2. input means for generating a feedback signal inresponse to the scanning illumination generated with said liquid crystaldevice,
 3. execution means for generating the scan control signal inresponse to the feedback signal under control of the program stored insaid main memory,
 4. output means for outputting the scan control signalunder control of the program stored in said main memory.
 37. The systemas set forth in claim 36 above, wherein said integrated circuit computerincludes an integrated circuit read only memory for storing a program.38. The system as set forth in claim 37 above, wherein said integratedcircuit computer includes an integrated circuit alterable memory forstoring operands.
 39. The system as set forth in claim 38 above, whereinsaid integrated circuit computer includes integrated circuit processinglogic for processing the operands stored in said alterable memory undercontrol of the program stored in said read only memory.
 40. A scanningsystem comprising:a high intensity illumination source for generatinghigh intensity source illumination; an electrical control device forgenerating sequential electrical scanning signals; and a liquid crystaldevice for controlling the high intensity source illumination togenerate high intensity scanning illumination under control of thesequential electrical scanning signals generated with said electricalcontrol device, wherein controlling of the high intensity sourceillumination with said liquid crystal device causes heating of saidliquid crystal device; and thermal means for removing heat from saidliquid crystal device.
 41. A scanner display system comprising:a highintensity illumination source for generating high intensity sourceillumination; a display control device for generating scanning controlsignals; a liquid crystal device for controlling the high intensitysource illumination to generate high intensity scanned displayillumination in response to the scanning control signals generated withsaid display control device; and means for circulating cooling fluid inthermal contact with said liquid crystal device for heat removaltherefrom.
 42. A scanner display system comprising:a high intensityillumination source for generating high intensity source illumination; ascanning control device for generating scanning control signals; aliquid crystal device for controlling the high intensity sourceillumination to generate high intensity scanned illumination in responseto the scanning control signals generated with said scanning controldevice; and means for providing forced air cooling of said liquidcrystal device.